Question

Bài 6: tìm cặp số x, y thỏa mãn đẳng thức sau:

a) 3( 2x -1)² + 7( 3y+5)² = 0

b) x²+y²-2x + 10y +26=0

Answer 1

`a, {(2x-1=0), (3y+5=0):}`

`<=> {(x=1/2), (y=-5/3):}`

`b, (x-1)^2 + (y+5)^2 = 0`

`<=> {(x=1), (y=-5):}`

Answer 2

a) P/t \(\Leftrightarrow\left\{{}\begin{matrix}2x-1=0\\3y+5=0\end{matrix}\right.\)  \(\Leftrightarrow\left\{{}\begin{matrix}x=\dfrac{1}{2}\\y=-\dfrac{5}{3}\end{matrix}\right.\)

b) P/t \(\Leftrightarrow\left(x^2-2x+1\right)+\left(y^2+10y+25\right)=0\)

\(\Leftrightarrow\left(x-1\right)^2+\left(y+5\right)^2=0\)

\(\Leftrightarrow\left\{{}\begin{matrix}x-1=0\\y+5=0\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}x=1\\y=-5\end{matrix}\right.\)