Question

X^2-25=(x+5)(3-2)

Answer 1

`x^2 -25=(x+5)(3-2)`

`<=>(x-5)(x+5)-(x+5)=0`

`<=>(x+5)(x-5-1)=0`

`<=>(x+5)(x-6)=0`

`<=>x+5=0` hoặc `x-6=0`

`<=>x=-5` hoặc `x=6`

Answer 2

`x^2-25=(x+5)(3-2)`

`<=> (x-5)(x+5) -(x+5)(3-2)=0`

`<=>(x+5)(x-5-3+2)=0`

`<=>(x+5)(x- 6)=0`

\(\Leftrightarrow\left[{}\begin{matrix}x+5=0\\x-6=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=-5\\x=6\end{matrix}\right.\)

vậy pt có nghiệm \(S=\left\{-5;6\right\}\)