Question

1)(2x-5)^2-(x+2)^2=0

2) (3x^2+10x-8)^2=(5x^2-2x+10)

3) (x^2-2x+1)-4=0

Answer 1

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

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

\(\Leftrightarrow\left(x-7\right)\left(3x-3\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=7\\x=1\end{matrix}\right.\)

Answer 2

Bài 2:

\(3x^2+10x-8=5x^2-2x+10\)

\(\Leftrightarrow 2x^2-12x+18=0\)

\(\Leftrightarrow x^2-6x+9=0\)

\(\Leftrightarrow (x-3)^2=0\Rightarrow x=3\)

Answer 3

Bài 3:

\((x^2-2x+1)-4=0\)

\(\Leftrightarrow (x-1)^2-2^2=0\)

\(\Leftrightarrow (x-1-2)(x-1+2)=0\Leftrightarrow (x-3)(x+1)=0\)

\(\Rightarrow \left[\begin{matrix} x=3\\ x=-1\end{matrix}\right.\)