Bài này thay x=3-2y vào pt 2
( có lẽ khi thay vào hơi rối )
Đúng 0
Bình luận (1)
Chương III - Hệ hai phương trình bậc nhất hai ẩn
Các câu hỏi tương tự
10. giải hpt bằng phương pháp thế:6) left{{}begin{matrix}2y-403x+y-4end{matrix}right.7) left{{}begin{matrix}4x-6y2x-dfrac{3}{2}ydfrac{1}{2}end{matrix}right.8) left{{}begin{matrix}dfrac{x}{3}+dfrac{y}{2}12x+3ydfrac{2}{5}end{matrix}right.9) left{{}begin{matrix}3x-2y2x+3y6end{matrix}right.10) left{{}begin{matrix}2x+3y24x-y-10end{matrix}right.11) left{{}begin{matrix}3x-2y32x-dfrac{4}{3}y1end{matrix}right.12) left{{}begin{matrix}5x+y32x+0,4y1,2end{matrix}right.giúp mk vs ạ mai mk học rồi
Đọc tiếp
10. giải hpt bằng phương pháp thế:
6) \(\left\{{}\begin{matrix}2y-4=0\\3x+y=-4\end{matrix}\right.\)
7) \(\left\{{}\begin{matrix}4x-6y=2\\x-\dfrac{3}{2}y=\dfrac{1}{2}\end{matrix}\right.\)
8) \(\left\{{}\begin{matrix}\dfrac{x}{3}+\dfrac{y}{2}=1\\2x+3y=\dfrac{2}{5}\end{matrix}\right.\)
9) \(\left\{{}\begin{matrix}3x-2=y\\2x+3y=6\end{matrix}\right.\)
10) \(\left\{{}\begin{matrix}2x+3y=2\\4x-y-1=0\end{matrix}\right.\)
11) \(\left\{{}\begin{matrix}3x-2y=3\\2x-\dfrac{4}{3}y=1\end{matrix}\right.\)
12) \(\left\{{}\begin{matrix}5x+y=3\\2x+0,4y=1,2\end{matrix}\right.\)
giúp mk vs ạ mai mk học rồi
GIẢI HPT
\(_{\left\{{}\begin{matrix}2\left(x+1\right)-\dfrac{y}{4}=10\\\dfrac{2x+3}{3-4x}=\dfrac{x-y+5}{6-2x+2y}\end{matrix}\right.\)
Giải hệ phương trình:
a) left{{}begin{matrix}2x-y3x+2y-1end{matrix}right.
b) left{{}begin{matrix}dfrac{3}{2}x-ydfrac{1}{2}3x-2y1end{matrix}right.
c) left{{}begin{matrix}5left(x+2yright)3x-12x+43left(x-5yright)-12end{matrix}right.
d) left{{}begin{matrix}dfrac{1}{x}-dfrac{1}{y}1dfrac{3}{x}+dfrac{4}{y}5end{matrix}right.
e) left{{}begin{matrix}dfrac{2x}{x+1}+dfrac{y}{y+1}sqrt{2}dfrac{x}{x+1}+dfrac{3y}{y+1}-1end{matrix}right.
Giúp mình với!!!
Đọc tiếp
Giải hệ phương trình:
a) \(\left\{{}\begin{matrix}2x-y=3\\x+2y=-1\end{matrix}\right.\)
b) \(\left\{{}\begin{matrix}\dfrac{3}{2}x-y=\dfrac{1}{2}\\3x-2y=1\end{matrix}\right.\)
c) \(\left\{{}\begin{matrix}5\left(x+2y\right)=3x-1\\2x+4=3\left(x-5y\right)-12\end{matrix}\right.\)
d) \(\left\{{}\begin{matrix}\dfrac{1}{x}-\dfrac{1}{y}=1\\\dfrac{3}{x}+\dfrac{4}{y}=5\end{matrix}\right.\)
e) \(\left\{{}\begin{matrix}\dfrac{2x}{x+1}+\dfrac{y}{y+1}=\sqrt{2}\\\dfrac{x}{x+1}+\dfrac{3y}{y+1}=-1\end{matrix}\right.\)
Giúp mình với!!!
giải hệ pt:9) left{{}begin{matrix}dfrac{7}{2x+y}+dfrac{4}{2x-y}74dfrac{3}{2x+y}+dfrac{2}{2x-y}32end{matrix}right.10) left{{}begin{matrix}x2y-12x-y5end{matrix}right.11) left{{}begin{matrix}3x-602y-x4end{matrix}right.12) left{{}begin{matrix}2x+y5x+7y9end{matrix}right.13) left{{}begin{matrix}dfrac{3}{x}-dfrac{4}{y}2dfrac{4}{x}-dfrac{5}{y}3end{matrix}right.14) left{{}begin{matrix}dfrac{1}{x}+dfrac{1}{y}dfrac{1}{12}dfrac{8}{x}+dfrac{15}{y}1end{matrix}right.15) left{{}begin{matrix}2sqrt{x-1}-sqrt{y-1}...
Đọc tiếp
giải hệ pt:
9) \(\left\{{}\begin{matrix}\dfrac{7}{2x+y}+\dfrac{4}{2x-y}=74\\\dfrac{3}{2x+y}+\dfrac{2}{2x-y}=32\end{matrix}\right.\)
10) \(\left\{{}\begin{matrix}x=2y-1\\2x-y=5\end{matrix}\right.\)
11) \(\left\{{}\begin{matrix}3x-6=0\\2y-x=4\end{matrix}\right.\)
12) \(\left\{{}\begin{matrix}2x+y=5\\x+7y=9\end{matrix}\right.\)
13) \(\left\{{}\begin{matrix}\dfrac{3}{x}-\dfrac{4}{y}=2\\\dfrac{4}{x}-\dfrac{5}{y}=3\end{matrix}\right.\)
14) \(\left\{{}\begin{matrix}\dfrac{1}{x}+\dfrac{1}{y}=\dfrac{1}{12}\\\dfrac{8}{x}+\dfrac{15}{y}=1\end{matrix}\right.\)
15) \(\left\{{}\begin{matrix}2\sqrt{x-1}-\sqrt{y-1}=1\\\sqrt{x-1}+\sqrt{y-1}=2\end{matrix}\right.\)
giúp mk vs ạ mai mk học rồi
Giải hệ phương trình: \(\left\{{}\begin{matrix}\dfrac{1}{\sqrt{2x^2+1}}+\dfrac{1}{\sqrt{2y^2+1}}=\dfrac{2}{\sqrt{1+2xy}}\\\sqrt{x\left(1-2x\right)}+\sqrt{y\left(1-2y\right)}=\dfrac{2}{9}\end{matrix}\right.\)
Giải hệ phương trình:
a)left{{}begin{matrix}dfrac{3x+2}{x-1}-dfrac{3y-1}{y+2}0dfrac{2}{x-1}+dfrac{3}{y+2}1end{matrix}right.
b)left{{}begin{matrix}dfrac{4x-5}{x+1}+dfrac{2y-3}{y-5}8dfrac{3}{x+1}-dfrac{2}{y-5}-1end{matrix}right.
c)left{{}begin{matrix}dfrac{x+y-2}{x+1}+dfrac{3-x}{y+1}dfrac{5}{4}dfrac{3left(x+y-2right)}{x+1}-dfrac{5-x+2y}{y+1}dfrac{3}{4}end{matrix}right.
d)left{{}begin{matrix}dfrac{x-y+1}{x-3}+dfrac{x+1}{y-3}dfrac{-7}{2}dfrac{2left(x-y+1right)}{x-3}-dfrac{x+y-2}{y-3}-dfrac{9}{2}...
Đọc tiếp
Giải hệ phương trình:
a)\(\left\{{}\begin{matrix}\dfrac{3x+2}{x-1}-\dfrac{3y-1}{y+2}=0\\\dfrac{2}{x-1}+\dfrac{3}{y+2}=1\end{matrix}\right.\)
b)\(\left\{{}\begin{matrix}\dfrac{4x-5}{x+1}+\dfrac{2y-3}{y-5}=8\\\dfrac{3}{x+1}-\dfrac{2}{y-5}=-1\end{matrix}\right.\)
c)\(\left\{{}\begin{matrix}\dfrac{x+y-2}{x+1}+\dfrac{3-x}{y+1}=\dfrac{5}{4}\\\dfrac{3\left(x+y-2\right)}{x+1}-\dfrac{5-x+2y}{y+1}=\dfrac{3}{4}\end{matrix}\right.\)
d)\(\left\{{}\begin{matrix}\dfrac{x-y+1}{x-3}+\dfrac{x+1}{y-3}=\dfrac{-7}{2}\\\dfrac{2\left(x-y+1\right)}{x-3}-\dfrac{x+y-2}{y-3}=-\dfrac{9}{2}\end{matrix}\right.\)
e)\(\left\{{}\begin{matrix}x^2-y^2+2y=1\\\left(x+y\right)^2-2x-2y=0\end{matrix}\right.\)
f)\(\left\{{}\begin{matrix}4x^2+y^2-4xy=4\\x^2+y^2-2\left(xy+8\right)=0\end{matrix}\right.\)
Giải hpt:
\(\left\{{}\begin{matrix}\dfrac{y^2-x^2}{\sqrt{x-1}}=2y-\sqrt{x-1}\\x^2+y^2=3x-1\end{matrix}\right.\)
giải hpt bằng phương pháp thế:9) left{{}begin{matrix}3x-2y2x+3y6end{matrix}right.10) left{{}begin{matrix}2x+3y24x-y-10end{matrix}right.11) left{{}begin{matrix}3x-2y32x-dfrac{4}{3}y1end{matrix}right.12) left{{}begin{matrix}5x+y32x+0,4y1,2end{matrix}right.giúp mk vs ạ mai mk học rồi
Đọc tiếp
giải hpt bằng phương pháp thế:
9) \(\left\{{}\begin{matrix}3x-2=y\\2x+3y=6\end{matrix}\right.\)
10) \(\left\{{}\begin{matrix}2x+3y=2\\4x-y-1=0\end{matrix}\right.\)
11) \(\left\{{}\begin{matrix}3x-2y=3\\2x-\dfrac{4}{3}y=1\end{matrix}\right.\)
12) \(\left\{{}\begin{matrix}5x+y=3\\2x+0,4y=1,2\end{matrix}\right.\)
giúp mk vs ạ mai mk học rồi
giải hpt \(\left\{{}\begin{matrix}2\left(x-2\right)^2+\dfrac{1}{\sqrt{y+5}}=3\\\left(x-2\right)^2-\dfrac{2}{\sqrt{y+5}}=-1\end{matrix}\right.\)