Các câu hỏi tương tự
cau 1 giai phuong trinh sau a) 7 x -14 0 b) ( 3x +1 ) ( 2x-2) 0 c) ( 3x -1 ) x-2 cau 2 giai bat phuong trinh va bieu dien truc nghiem tren truc so a ) 2x+5 hoac ( )9 b) 3x +4 5x-3 c ) 3x-1 tren 4 2cau 3 cho tam giac a bc vuong goc tai a , co ab 12 cm , ac 16 cm . ke duong cao ah ( hthuoc bc )a) chung minh : tam giac hba thuoc tam giac abc b) tinh do dai bc,ah c) he ad,de,df,la phan giac lan luot cua cac goc bac,hdb,adc,c thuoc a b , d thuoc bc, f thuoc ab chung minh rang : ea phan eb db...
Đọc tiếp
cau 1 giai phuong trinh sau
a) 7 x -14 =0
b) ( 3x +1 ) ( 2x-2) =0
c) ( 3x -1 ) = x-2
cau 2 giai bat phuong trinh va bieu dien truc nghiem tren truc so
a ) 2x+5 < hoac ( = )9
b) 3x +4 <5x-3
c ) 3x-1 tren 4 >2
cau 3 cho tam giac a bc vuong goc tai a , co ab = 12 cm , ac =16 cm . ke duong cao ah ( hthuoc bc )
a) chung minh : tam giac hba thuoc tam giac abc
b) tinh do dai bc,ah
c) he ad,de,df,la phan giac lan luot cua cac goc bac,hdb,adc,c thuoc a b , d thuoc bc, f thuoc ab
chung minh rang : ea phan eb = db phan dc , fc phan fa = 1
ban nao nhanh minh k cho 10 k
1. Cho hinh thang ABCD , phan giac cua goc A cat duong cheo BD tai E va phan giac goc B cat AC tai F . Chung minh EF //AB?2.Cho tam giac ABC , cac tia phan giac cua goc B va goc C cat nhau tai O . Tu A ve duong thang vuong goc voi OA cat BO , CO lan luot tai M va N . Chung minh BM vuong goc voi BN , CM vuong goc voi CN?3.Cho goc vuong xOy ,vaf tam giac ABC vuong tai A (B thuoc Ox ,AC thuoc Oy,A va O nam tren hai nua mat phang doi nhau co bo la BC ).chung minh OA la tia phan gic cua xOy ?cac ban...
Đọc tiếp
1. Cho hinh thang ABCD , phan giac cua goc A cat duong cheo BD tai E va phan giac goc B cat AC tai F . Chung minh EF //AB?
2.Cho tam giac ABC , cac tia phan giac cua goc B va goc C cat nhau tai O . Tu A ve duong thang vuong goc voi OA cat BO , CO lan luot tai M va N . Chung minh BM vuong goc voi BN , CM vuong goc voi CN?
3.Cho goc vuong xOy ,vaf tam giac ABC vuong tai A (B thuoc Ox ,AC thuoc Oy,A va O nam tren hai nua mat phang doi nhau co bo la BC ).chung minh OA la tia phan gic cua xOy ?
cac ban giup mik nha
Chứng minh rằng nếu ab+bc+ac=abc và a+b+c =0 thì 1/a^2+1/b^2+1/c^2=1
Giúp mik với nha !!!!!
Cho tam giac ABC co AB=12cm,AC=20cm va BC=28cm.Duong phan giac cua goc A cat BC tai D
a) tinh BD ,DC
b) ve DE song song voi BC tinh DE
theo mk thay dau bai nay hoi sai ban nao thay vay thi noi mk bit nha. neu giai dk ve hinh cho mk nha
ban nao giup minh bai 49 sgk toan 8 trang 93voi nhung k can lam phan a va b ma ap dung no de giai tiep phan c va d tiep
c) goi AN giao BC tai P.Chung minh p la trung diem cua BC
d) chung minh AC,BD,KI dong qui
giup minh voi minh can gap
Cho tam giac ABC co do dai BC=a va M la trung diem cua AB. Tia Mx //BC cat AC tai N
a, c/m N la trung diem cua AC
b, tinh do dai doan thang MN theo a.
Bai 2 cho tam giac ABC can tai A co M la trung diem cua BC.Ke Mx//AC cat AB tai E,ke My //AB cat AC tai F.
1, E,F la trung diem cua AB va AC
2,EF=1/2BC
3,ME=MF, AE=AF
Moi nguoi giai mot bai ho minh nha.minh dang can gap
1. a/x(x-3)-x^2=6
b/(x-2)^2 +x(3-x)=5
c/(x-2)(x+1)=x^2=6
d/(x-2)(x+2)-x(x+4)=5
e/(x-3)(x^2+3x+9)-x^3+x=7
f/x^2+3x+2=0
h/(x-1)(x-5)+(3-x)(1+2)=7
l/(x+2)^2-(x-1)^2=0
k/(x+3)(x-3)-(x-1)^2=6
Giup minh nha !! Hoi dai nhung giai dc phan nao thi giai !!
Dung viet ket qua luon nha !! Giai ra ho mk !!
Cho ab+bc+ac=1,a,b,c thuoc Q CMR:A=(a^2+1)(b^2+1)(c^2+1) la binh phuong cua 1 so huu ti
Giai ho minh de nay voi cac p:cho tam giac ABC can tai A,duong cao AH,AB=8cm,BC=10cm
a,tinh BH,AH
b,goi BK va CI la cac duong phan giac cua tam giac ABC,chung minh rang tu giac BIKC la hinh thang can