{"segment":[{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"T\u1ed5ng ba g\u00f3c c\u1ee7a m\u1ed9t tam gi\u00e1c b\u1eb1ng: ","select":["A. $90^{o} $ ","B. $120^{o} $ ","C. $180^{o} $ ","D. $150^{o} $ "],"explain":" T\u1ed5ng ba g\u00f3c c\u1ee7a m\u1ed9t tam gi\u00e1c b\u1eb1ng $180^{o} $ . <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C. <\/span> ","column":4}]}],"id_ques":1761},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["180"]]],"list":[{"point":5,"width":20,"content":"","type_input":"","ques":"Cho h\u00ecnh v\u1ebd sau: <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-01.png' \/><\/center> <br\/> \u0110i\u1ec1n k\u1ebft qu\u1ea3 v\u00e0o t\u1ed5ng sau: $\\widehat{A} + \\widehat{B} + \\widehat{C} + \\widehat{D} + \\widehat{E} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^o $","explain":"<span class='basic_left'>\u00c1p d\u1ee5ng t\u00ednh ch\u1ea5t g\u00f3c ngo\u00e0i c\u1ee7a tam gi\u00e1c:<br\/> $\\triangle MBD $ c\u00f3: $\\widehat{M_{1}} = \\widehat{B} + \\widehat{D}; $ <br\/> $\\triangle NCE $ c\u00f3: $\\widehat{N_{1}} = \\widehat{C} + \\widehat{E} $ <br\/> M\u1eb7t kh\u00e1c $\\triangle AMN $ c\u00f3 $\\widehat{A} + \\widehat{M_{1}} + \\widehat{N_{1}} = 180^{o} $ <br\/> $\\Rightarrow \\widehat{A} + \\widehat{B} + \\widehat{C} + \\widehat{D} + \\widehat{E} = 180^{o} $ <br\/><br\/> <span class='basic_pink'> V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0: 180 <\/span>"}]}],"id_ques":1762},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["80"]]],"list":[{"point":5,"width":20,"content":"","type_input":"","ques":"Cho h\u00ecnh v\u1ebd, bi\u1ebft: $\\widehat{A} = 40^{o}; \\widehat{C} = 60^{o}; OC = OD $ <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-02.png' \/><\/center> <br\/> T\u00ednh s\u1ed1 \u0111o g\u00f3c $B$. <br\/> <b>\u0110\u00e1p \u00e1n: <\/b> $\\widehat{B} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^o $ ","explain":"<span class='basic_left'>$\\triangle OCD $ c\u00f3 $OC = OD, \\widehat{C} = 60^{o} \\Rightarrow \\triangle OCD $ \u0111\u1ec1u <br\/> $\\Rightarrow \\widehat{COD} = \\widehat{BOA} = 60^{o} $ (\u0111\u1ed1i \u0111\u1ec9nh) <br\/> $\\triangle OAB $ c\u00f3: $\\widehat{A} + \\widehat{AOB} + \\widehat{B} = 180^{o} $ <br\/> $\\Rightarrow 40^{o} + 60^{o} + \\widehat{B} = 180^{o} \\\\ \\Rightarrow \\widehat{B} = 80^{o} $<br\/><br\/> <span class='basic_pink'> V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0: 80<\/span> "}]}],"id_ques":1763},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["30"]]],"list":[{"point":5,"width":20,"content":"","type_input":"","ques":"Cho h\u00ecnh v\u1ebd, bi\u1ebft: $AB = BE = EA = ED; BD = DC; \\widehat{BED} = 90^{o} $ <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-03.png' \/><\/center> <br\/> T\u00ednh s\u1ed1 \u0111o g\u00f3c $BDC$. <br\/> <b> \u0110\u00e1p \u00e1n: <\/b> $\\widehat{BDC} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^o $ ","explain":"<span class='basic_left'> $ \\triangle AEB $ c\u00f3 $EA = AB = BE \\Rightarrow \\triangle AEB $ \u0111\u1ec1u $\\Rightarrow \\widehat{EBA} = 60^{o} $ <br\/> $\\triangle EDB $ vu\u00f4ng c\u00e2n t\u1ea1i E n\u00ean $\\widehat{EBD} = 45^{o} $ <br\/> Ta c\u00f3: $\\widehat{ABE} + \\widehat{EBD} + \\widehat{DBC} = 180^{o} \\\\ \\Rightarrow 60^{o} + 45^{o} + \\widehat{DBC} = 180^{o} \\\\ \\Rightarrow \\widehat{DBC} = 75^{o} $ <br\/> $\\triangle BDC $ c\u00e2n t\u1ea1i $D (BD = CD)$ <br\/> $\\Rightarrow \\widehat{BCD} = \\widehat{DBC} = 75^{o} $ <br\/> Do \u0111\u00f3 $\\widehat{BDC} = 180^{o} - 75^{o} - 75^{o} = 30^{o} $ <br\/><br\/> <span class='basic_pink'>V\u1eady c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0: 30 <\/span> "}]}],"id_ques":1764},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00fang hay sai","title_trans":"","temp":"true_false","correct":[["t","t","t"]],"list":[{"point":5,"ques":"<span class='basic_left'> Cho h\u00ecnh v\u1ebd, bi\u1ebft: $\\widehat{EAD} = \\widehat{HAD}, HB \\perp AE, EC \\perp AH $. Khi \u0111\u00f3: ","image":"https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-04.png","col_name":["","\u0110\u00fang","Sai"],"arr_ques":["$\\triangle ABD = \\triangle ACD $","$\\triangle DBE = \\triangle DCH$","$\\triangle ABH = \\triangle ACE $"],"explain":["<span class='basic_left'> 1. X\u00e9t hai tam gi\u00e1c $\\triangle ABD $ v\u00e0 $\\triangle ACD $ c\u00f3: <br\/> + $\\widehat{ABD} = \\widehat{ACD} = 90^{o} $ <br\/> + $AD$ l\u00e0 c\u1ea1nh chung <br\/> + $\\widehat{BAD} = \\widehat{CAD} $ (gi\u1ea3 thi\u1ebft) <br\/> $\\Rightarrow \\triangle ABD = \\triangle ACD $ (c\u1ea1nh huy\u1ec1n - g\u00f3c nh\u1ecdn) <\/span>","<span class='basic_left'> 2. X\u00e9t $\\triangle BDE $ v\u00e0 $\\triangle CDH $ c\u00f3: <br\/> + $\\widehat{DBE} = \\widehat{DCH (= 90^{o})}$ <br\/> + $BD = CD$ (v\u00ec $\\triangle ABD = \\triangle ACD $)<br\/> + $\\widehat{BDE} = \\widehat{CDH}$ (\u0111\u1ed1i \u0111\u1ec9nh) <br\/> T\u1eeb \u0111\u00f3 suy ra $\\triangle BDE = \\triangle CDH (g.c.g) $ <\/span>","<span class='basic_left'> 3 - X\u00e9t $\\triangle ABH $ v\u00e0 $\\triangle ACE $, ta c\u00f3: <br\/> + $\\widehat{ABH} = \\widehat{ACE} (= 90^{o}) $ <br\/>+ $ AB = AC$ (v\u00ec $\\triangle ABD = \\triangle ACD $) <br\/> + $\\widehat{EAH}$ chung <br\/> V\u1eady $\\triangle ABH = \\triangle ACE (g.c.g) $ <\/span>"]}]}],"id_ques":1765},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[2]],"list":[{"point":5,"ques":"<span class='basic_left'> Cho h\u00ecnh v\u1ebd, bi\u1ebft $\\widehat{B} = 50^{o}, \\widehat{C} = 20^{o} $ <br\/> S\u1ed1 \u0111o c\u1ee7a c\u00e1c g\u00f3c $x$ v\u00e0 $y$ l\u00e0: <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-05.png' \/><\/center>","select":["A. $x = 70^{o}, y = 70^{o} $ ","B. $x = 70^{o}, y = 160^{o} $ ","C. $x = 160^{o}, y = 70^{o} $ ","D. $x = 20^{o}, y = 50^{o} $ "],"explain":"<span class='basic_left'> Tam gi\u00e1c $ABC $ c\u00f3 $\\widehat{A} + \\widehat{B} + \\widehat{C} = 180^{o} \\\\ \\Rightarrow \\widehat{A} = 180^{o} - 50^{o} - 20^{o} = 110^{o} $ <br\/> $\\Rightarrow x = 180^{o} - 110^{o} = 70^{o} $ <br\/> $y = 180^{o} - 20^{o} = 160^{o} $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 B. <\/span> ","column":2}]}],"id_ques":1766},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"Cho $\\triangle DEF = \\triangle HIK $ trong \u0111\u00f3: <br\/> $DE = 4cm$, $\\widehat{E} = 50^{o}$ , $IK = 6cm $. Suy ra: ","select":["A. $HI = 4cm; \\widehat{I} = 50^{o}; EF = 6cm $ ","B. $EF = 4cm; \\widehat{I} = 50^{o}; HI = 6cm$ ","C. $EF = 4cm; \\widehat{I} = 120^{o}; HI = 6cm $ ","D. $DF = 10cm; \\widehat{I} = 50^{o}; EF = 2cm$ "],"explain":"<span class='basic_left'> Ta c\u00f3: $\\triangle DEF = \\triangle HIK $ n\u00ean: <br\/> $DE = HI = 4cm \\\\ EF = IK = 6cm \\\\ \\widehat{E} = \\widehat{I} = 50^{o} $<br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 A. <\/span> ","column":2}]}],"id_ques":1767},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"<span class='basic_left'> Cho $\\triangle ABC$ v\u00e0 $\\triangle DEF $ trong \u0111\u00f3: <br\/> $AB = DF, DE = AC, BC = EF$.<br\/> Ta suy ra \u0111\u01b0\u1ee3c: <\/span>","select":["A. $\\widehat{A} = \\widehat{D}; \\widehat{B} = \\widehat{E}; \\widehat{C} = \\widehat{F} $ ","B. $\\widehat{A} = \\widehat{E}; \\widehat{B} = \\widehat{D}; \\widehat{C} = \\widehat{F} $ ","C. $\\widehat{A} = \\widehat{D}; \\widehat{B} = \\widehat{F}; \\widehat{C} = \\widehat{E} $ ","D. $\\widehat{A} = \\widehat{F}; \\widehat{B} = \\widehat{D}; \\widehat{C} = \\widehat{E} $"],"explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-06.png' \/><\/center> $\\triangle ABC$ v\u00e0 $\\triangle DEF $ c\u00f3: <br\/> + $AB = DF$ <br\/> + $ DE = AC$ <br\/> + $ BC = EF$ <br\/>$ \\triangle ABC = \\triangle DFE \\,(c-c-c) $ <br\/> $ \\Rightarrow \\widehat{A} = \\widehat{D}; \\widehat{B} = \\widehat{F}; \\widehat{C} = \\widehat{E} $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C. <\/span> ","column":2}]}],"id_ques":1768},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"<span class='basic_left'> Cho h\u00ecnh v\u1ebd, bi\u1ebft I l\u00e0 trung \u0111i\u1ec3m chung c\u1ee7a hai \u0111o\u1ea1n th\u1eb3ng $HE$ v\u00e0 $KD$, $\\widehat{IDE} = 50^{o}, \\widehat{HID} = 85^{o} $ <br\/> S\u1ed1 \u0111o c\u1ee7a g\u00f3c $IHK$ b\u1eb1ng: <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-07.png' \/><\/center> <\/span> ","select":["A. $85^{o} $ ","B. $95^{o} $ ","C. $35^{o} $ ","D. $50^{o} $ "],"explain":"<span class='basic_left'> Ta c\u00f3 $\\widehat{HID} $ l\u00e0 g\u00f3c ngo\u00e0i c\u1ee7a $\\triangle IDE $ n\u00ean: <br\/> $\\widehat{D} + \\widehat{E} = \\widehat{HID} \\\\ \\Rightarrow \\widehat{E} = 85^{o} - 50^{o} = 35^{o} $ <br\/> X\u00e9t $\\triangle IHK $ v\u00e0 $\\triangle IED$ c\u00f3: <br\/> + $IK = ID$ (gi\u1ea3 thi\u1ebft)<br\/> + $\\widehat{HIK} = \\widehat{EID} $ (\u0111\u1ed1i \u0111\u1ec9nh) <br\/> + $ IH = IE$ (gi\u1ea3 thi\u1ebft) <br\/> Do \u0111\u00f3 $\\triangle IHK = \\triangle IED (c.g.c) $ <br\/> $\\Rightarrow \\widehat{H} = \\widehat{E} = 35^{o} $ <br\/> Hay $\\widehat{IHK} = 35^{o} $ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C. <\/span> ","column":4}]}],"id_ques":1769},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"<b>T\u00ecm c\u00e2u tr\u1ea3 l\u1eddi sai.<\/b> <br\/> Cho h\u00ecnh v\u1ebd, bi\u1ebft $AB \/\/ CD, AD \/\/ BC$. Ta ch\u1ee9ng minh \u0111\u01b0\u1ee3c: <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-08a.png' \/><\/center> ","select":["A. $AB = CD$ ","B. $AD = BC$ ","C. $\\widehat{BAD} = \\widehat{DCB}$ ","D. $\\triangle ABC = \\triangle ADC $ "],"explain":"<span class='basic_left'> <span class='basic_pink'> C\u00e2u tr\u1ea3 l\u1eddi sai l\u00e0 D. <\/span> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-08.png' \/><\/center> Do $AB \/\/CD$ n\u00ean $\\widehat{A_1}=\\widehat{C_1}$ (so le trong) <br\/> Do $AD \/\/BC$ n\u00ean $\\widehat{A_2}=\\widehat{C_2}$ (so le trong) <br\/> $\\Rightarrow \\widehat{A_1}+\\widehat{A_2}=\\widehat{C_1}+\\widehat{C_2}$ <br\/> Hay $\\widehat{BAD}=\\widehat{DCB}$ <br\/> $\\Rightarrow$ <b> C\u00e2u C \u0111\u00fang<\/b> <br\/> X\u00e9t hai tam gi\u00e1c $ABC$ v\u00e0 $CDA$ c\u00f3: <br\/> + $\\widehat{A_1}=\\widehat{C_1}$ (ch\u1ee9ng minh tr\u00ean) <br\/> + $AC$ chung <br\/> + $\\widehat{A_2}=\\widehat{C_2}$ (ch\u1ee9ng minh tr\u00ean) <br\/> $\\Rightarrow \\triangle ABC = \\triangle CDA $ (g - c - g) <br\/> $\\Rightarrow AB=CD; BC=AD$ (c\u00e1c c\u1eb7p c\u1ea1nh t\u01b0\u01a1ng \u1ee9ng) <br\/> $\\Rightarrow$ <b> C\u00e2u A v\u00e0 B \u0111\u00fang <\/b> <br\/> <b> C\u00e2u D sai <\/b> <\/span> ","column":2}]}],"id_ques":1770},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"<b> Kh\u1eb3ng \u0111\u1ecbnh n\u00e0o sau \u0111\u00e2y sai <\/b> ","select":["A. Tam gi\u00e1c c\u00f3 ba g\u00f3c \u0111\u1ec1u nh\u1ecdn g\u1ecdi l\u00e0 tam gi\u00e1c nh\u1ecdn. ","B. Tam gi\u00e1c c\u00f3 m\u1ed9t g\u00f3c t\u00f9 g\u1ecdi l\u00e0 tam gi\u00e1c t\u00f9. ","C. Tam gi\u00e1c c\u00e2n l\u00e0 tam gi\u00e1c c\u00f3 hai c\u1ea1nh b\u1eb1ng nhau. ","D. Trong tam gi\u00e1c c\u00e2n ba g\u00f3c b\u1eb1ng nhau. "],"explain":" V\u00ec: <br\/> Trong tam gi\u00e1c c\u00e2n hai g\u00f3c \u1edf \u0111\u00e1y b\u1eb1ng nhau. <br\/> V\u1eady kh\u1eb3ng \u0111\u1ecbnh D l\u00e0 sai <br\/> <span class='basic_pink'> Ch\u1ecdn \u0111\u00e1p \u00e1n D. <\/span> ","column":1}]}],"id_ques":1771},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[1]],"list":[{"point":5,"ques":"<b> Kh\u1eb3ng \u0111\u1ecbnh n\u00e0o sau \u0111\u00e2y sai <\/b> ","select":["A. Trong tam gi\u00e1c \u0111\u1ec1u c\u00e1c g\u00f3c b\u1eb1ng nhau v\u00e0 b\u1eb1ng $90^{o}. $ ","B. Tam gi\u00e1c c\u00f3 m\u1ed9t g\u00f3c vu\u00f4ng g\u1ecdi l\u00e0 tam gi\u00e1c vu\u00f4ng. ","C. Tam gi\u00e1c vu\u00f4ng c\u00e2n l\u00e0 tam gi\u00e1c vu\u00f4ng c\u00f3 hai c\u1ea1nh g\u00f3c vu\u00f4ng b\u1eb1ng nhau. ","D. Trong tam gi\u00e1c vu\u00f4ng c\u00e2n c\u00f3 hai g\u00f3c nh\u1ecdn b\u1eb1ng nhau v\u00e0 b\u1eb1ng $45^{o} $. "],"explain":" <span class='basic_left'> V\u00ec: <br\/> Trong tam gi\u00e1c \u0111\u1ec1u c\u00e1c g\u00f3c b\u1eb1ng nhau v\u00e0 b\u1eb1ng $60^{o} $ <br\/> V\u1eady kh\u1eb3ng \u0111\u1ecbnh A l\u00e0 sai <br\/> <span class='basic_pink'> Ch\u1ecdn \u0111\u00e1p \u00e1n A. <\/span> ","column":1}]}],"id_ques":1772},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["44"],["66"]]],"list":[{"point":5,"width":40,"content":"","type_input":"","ques":"<span class='basic_left'> Tam gi\u00e1c $ABC$ c\u00f3 $\\widehat{B} = 70^{o} $ v\u00e0 $3\\widehat{A} = 2\\widehat{C} $ <br\/> T\u00ednh s\u1ed1 \u0111o g\u00f3c $A$ v\u00e0 g\u00f3c $C$. <br\/> <b> \u0110\u00e1p \u00e1n: <\/b> <br\/> $\\widehat{A} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^{o} \\\\ \\widehat{C} = \\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{}^{o} $ ","explain":"<span class='basic_left'> Trong tam gi\u00e1c $ABC$ c\u00f3: $\\widehat{A} + \\widehat{B} + \\widehat{C} = 180^{o} \\\\ \\Leftrightarrow \\widehat{A} + 70^{o} + \\widehat{C} = 180^{o} \\\\ \\Leftrightarrow \\widehat{A} + \\widehat{C} = 110^{o} $ <br\/> Theo b\u00e0i c\u00f3 $3\\widehat{A} = 2\\widehat{C} \\Leftrightarrow \\dfrac{\\widehat{A} }{2} = \\dfrac{\\widehat{C}}{3} = \\dfrac{\\widehat{A} +\\widehat{C} }{2+3} = \\dfrac{110^{o}}{5} = 22^{o} $ <br\/> V\u1eady $\\widehat{A} = 2.22^{o} = 44^{o} \\\\ \\widehat{C} = 3.22^{o} = 66^{o} $ <br\/> <span class='basic_pink'>\u0110\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u1ea7n l\u01b0\u1ee3t l\u00e0: 44 v\u00e0 66<\/span><\/span><\/span> <br\/>"}]}],"id_ques":1773},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"<span class='basic_left'> Cho h\u00ecnh v\u1ebd, bi\u1ebft $AB \/\/ CD$ <br\/> Ta t\u00ednh \u0111\u01b0\u1ee3c t\u1ed5ng $x + y$ b\u1eb1ng: <br\/> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-09.jpg' \/> <\/center> ","select":["A. $120^{o} $ ","B. $160^{o} $ ","C. $150^{o} $ ","D. $140^{o} $ "],"explain":"<center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-09.jpg' \/> <\/center><span class='basic_left'> V\u00ec $AB \/\/ CD$ n\u00ean $\\widehat{A} = \\widehat{ACD} $ (so le trong) <br\/> $\\Rightarrow y = 100^{o} $ <br\/> Tam gi\u00e1c $ABC$ c\u00f3: <br\/> $\\widehat{A} + \\widehat{B} + x = 180^{o} \\\\ \\Rightarrow x = 180^{o} - (\\widehat{A} + \\widehat{B}) \\\\ = 180^{o} - (100^{o} + 40^{o}) \\\\ = 40^{o} $ <br\/> V\u1eady $x + y = 100^{o} + 40^{o} = 140^{o}$ <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 D. <\/span>","column":4}]}],"id_ques":1774},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":" <b>T\u00ecm c\u00e2u tr\u1ea3 l\u1eddi sai <\/b> <br\/> Cho tam gi\u00e1c $ABC $ vu\u00f4ng t\u1ea1i A. Ta c\u00f3: <\/span> ","select":["A. $\\widehat{A} = \\widehat{B} + \\widehat{C} $ ","B. $\\widehat{B} + \\widehat{C} = 90^{o} $ ","C. Hai g\u00f3c $\\widehat{B} $ v\u00e0 $\\widehat{C}$ ph\u1ee5 nhau. ","D. Hai g\u00f3c $\\widehat{B} $ v\u00e0 $\\widehat{C}$ b\u00f9 nhau. "],"hint":"Trong m\u1ed9t tam gi\u00e1c vu\u00f4ng hai g\u00f3c nh\u1ecdn ph\u1ee5 nhau. ","explain":"<span class='basic_left'> Tam gi\u00e1c $ ABC$ vu\u00f4ng t\u1ea1i A, khi \u0111\u00f3: $\\widehat{A} = 90^{o} \\\\ \\widehat{B} + \\widehat{C} = 90^{o} $ <br\/> Hai g\u00f3c $\\widehat{B} $ v\u00e0 $\\widehat{C}$ ph\u1ee5 nhau. <br\/> <br\/> <span class='basic_pink'> \u0110\u00e1p \u00e1n sai l\u00e0 D. <\/span> <\/span>","column":2}]}],"id_ques":1775},{"time":24,"part":[{"title":"\u0110i\u1ec1n t\u1eeb th\u00edch h\u1ee3p v\u00e0o ch\u1ed7 tr\u1ed1ng","title_trans":"","temp":"fill_the_blank","correct":[[["30"]]],"list":[{"point":5,"width":40,"content":"","type_input":"","ques":"<span class='basic_left'> Cho $\\triangle ABC = \\triangle DEF $. Bi\u1ebft $AB = 8cm, BC = 12cm, DF = 10cm$. <br\/> Chu vi c\u1ee7a tam gi\u00e1c $ABC$ l\u00e0: $\\FormInput[40][bl_elm_true basic_elm basic_blank basic_blank_part]{} (cm)$ ","hint":"\u0110i t\u00ecm \u0111\u1ed9 d\u00e0i c\u1ee7a c\u1ea1nh $AC$ r\u1ed3i t\u00ednh chu vi tam gi\u00e1c $ABC$","explain":" <span class='basic_left'> Ta c\u00f3: $\\triangle ABC = \\triangle DEF $ n\u00ean $DF = AC = 10cm$ <br\/> Chu vi c\u1ee7a tam gi\u00e1c $ABC$ l\u00e0: <br\/> $AB + BC + AC = 8 + 12 + 10 = 30 (cm)$ <br\/><br\/><span class='basic_pink'> \u0110\u00e1p \u00e1n c\u1ea7n \u0111i\u1ec1n v\u00e0o \u00f4 tr\u1ed1ng l\u00e0: 30<\/span> "}]}],"id_ques":1776},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[3]],"list":[{"point":5,"ques":"<span class='basic_left'> Cho h\u00ecnh d\u01b0\u1edbi \u0111\u00e2y. N\u1ebfu th\u00eam m\u1ed9t \u0111i\u1ec1u ki\u1ec7n \u0111\u1ec3 $\\triangle ABC = \\triangle ADC $ theo tr\u01b0\u1eddng h\u1ee3p c\u1ea1nh - g\u00f3c - c\u1ea1nh th\u00ec \u0111i\u1ec1u ki\u1ec7n \u0111\u00f3 l\u00e0: <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-10.png' \/><\/center> ","select":[" A. $BC = DC $ "," B. $\\widehat{ABC} = \\widehat{ADC} $"," C. $\\widehat{BAC} = \\widehat{DAC} $ ","D. $\\widehat{BCA} = \\widehat{DCA} $ "],"explain":"<span class='basic_left'> X\u00e9t hai tam gi\u00e1c $ABC$ v\u00e0 $ADC$ c\u00f3: <br\/> + $AB=AD$ (gi\u1ea3 thi\u1ebft) <br\/> + $AC$ chung <br\/> Do \u0111\u00f3 \u0111\u1ec3 $\\triangle ABC = \\triangle ADC $ (c - g - c) th\u00ec ph\u1ea3i th\u00eam c\u1eb7p g\u00f3c t\u1ea1o b\u1edfi c\u00e1c c\u1eb7p c\u1ea1nh \u0111\u00e3 n\u00eau \u1edf tr\u00ean <br\/> T\u1ee9c l\u00e0 th\u00eam $\\widehat{BAC} = \\widehat{DAC} $ <br\/><span class='basic_pink'>\u0110\u00e1p \u00e1n \u0111\u00fang l\u00e0 C. <\/span>","column":2}]}],"id_ques":1777},{"time":9,"part":[{"title":"Ch\u1ecdn <u>nh\u1eefng<\/u> \u0111\u00e1p \u00e1n \u0111\u00fang","title_trans":"Ch\u1ecdn \u0111\u01b0\u1ee3c nhi\u1ec1u \u0111\u00e1p \u00e1n","temp":"checkbox","correct":[["1","2","4"]],"list":[{"point":5,"ques":"$\\triangle OAC = \\triangle OBD $ theo tr\u01b0\u1eddng h\u1ee3p g\u00f3c-c\u1ea1nh-g\u00f3c n\u1ebfu c\u00f3: <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-11.png' \/><\/center> ","column":2,"number_true":3,"select":["$\\widehat{AOB}$ chung","$OA = OB$","$OD = OC$","$\\widehat{OAC} = \\widehat{OBD} $"],"explain":"<span class='basic_left'> X\u00e9t $\\triangle OAC $ v\u00e0 $\\triangle OBD $ c\u00f3: <br\/> + $\\widehat{AOB}$ chung <br\/> + $OA = OB$ <br\/> + $\\widehat{OAC} = \\widehat{OBD}$ <br\/> th\u00ec $\\triangle OAC = \\triangle OBD (g.c.g)$ "}]}],"id_ques":1778},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"<span class='basic_left'> <b>Ch\u1ecdn c\u00e2u tr\u1ea3 l\u1eddi sai <\/b> <br\/> Cho tam gi\u00e1c $ABC$ c\u00e2n t\u1ea1i A v\u00e0 tam gi\u00e1c $A'B'C'$ c\u00e2n t\u1ea1i A', bi\u1ebft $AB = A'B'$. <br\/> B\u1ed5 sung th\u00eam m\u1ed9t \u0111i\u1ec1u ki\u1ec7n \u0111\u1ec3 $\\triangle ABC = \\triangle A'B'C' $ l\u00e0: ","select":["A. $BC = B'C'$ ","B. $\\widehat{A} = \\widehat{A'} $ ","C. $\\widehat{B} = \\widehat{B'} $ ","D. $AB = B'C' $ "],"explain":" <span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-12.png' \/><\/center> A. \u0110\u00fang. Khi \u0111\u00f3 $\\triangle ABC = \\triangle A'B'C' (c.c.c) $ <br\/> B. \u0110\u00fang. Khi \u0111\u00f3 $\\triangle ABC = \\triangle A'B'C' (c.g.c) $ <br\/> C. \u0110\u00fang. Khi \u0111\u00f3 $\\triangle ABC = \\triangle A'B'C' (c.g.c) $ ho\u1eb7c (g.c.g) <br\/> D. Sai. Kh\u00f4ng \u0111\u1ee7 \u0111i\u1ec1u ki\u1ec7n \u0111\u1ec3 hai tam gi\u00e1c b\u1eb1ng nhau. <br\/> V\u00ec khi \u0111\u00f3 $\\Delta A'B'C'$ l\u00e0 tam gi\u00e1c \u0111\u1ec1u nh\u01b0ng $\\Delta ABC$ ch\u01b0a ch\u1eafc \u0111\u00e3 l\u00e0 tam gi\u00e1c \u0111\u1ec1u. <br\/><br\/> <span class='basic_pink'> V\u1eady c\u00e2u tr\u1ea3 l\u1eddi sai l\u00e0 D. <\/span> ","column":2}]}],"id_ques":1779},{"time":24,"part":[{"title":"L\u1ef1a ch\u1ecdn \u0111\u00e1p \u00e1n \u0111\u00fang nh\u1ea5t","title_trans":"","temp":"multiple_choice","correct":[[4]],"list":[{"point":5,"ques":"<b>T\u00ecm c\u00e2u tr\u1ea3 l\u1eddi sai: <\/b><br\/> Tam gi\u00e1c $DHK$ vu\u00f4ng t\u1ea1i D khi: ","select":["A. $\\widehat{H} + \\widehat{K} = 90^{o} $","B. $DH^{2} + DK^{2} = HK^{2} $","C. $\\widehat{D} = \\widehat{H} + \\widehat{K} $ ","D. $DH^{2} + HK^{2} = DK^{2} $ "],"hint":"V\u1ebd h\u00ecnh r\u1ed3i t\u00ecm ra \u0111\u00e1p \u00e1n. ","explain":"<span class='basic_left'> <center><img src='https://www.luyenthi123.com/file/luyenthi123/lop7/toan/hinhhoc/bai16/lv1/img\/H7B16-13.png' \/><\/center> Ta c\u00f3 $\\triangle DHK $ vu\u00f4ng t\u1ea1i D n\u00ean: <br\/> A. $\\widehat{H} + \\widehat{K} = 90^{o} $ <br\/> B. Theo \u0111\u1ecbnh l\u00ed Py-ta-go c\u00f3: $DH^{2} + DK^{2} = HK^{2} $ <br\/> C. $\\widehat{D} = \\widehat{H} + \\widehat{K} = 90^{o}$ <br\/> C\u00e2u tr\u1ea3 l\u1eddi sai l\u00e0 D. ","column":2}]}],"id_ques":1780}],"lesson":{"save":0,"level":1}}