Giải phương trình (2x+5)2=(x+2)2

* Hướng dẫn giải

$\begin{array}{l}{\left(2x+5\right)}^2={\left(x+2\right)}^2\iff {\left(2x+5\right)}^2-{\left(x+2\right)}^2=0\\ \iff \left(2x+5-x-2\right)\left(2x+5+x+2\right)=0\iff \left(x+3\right)\left(3x+7\right)=0\\ \iff \left[\begin{array}{l}x+3=0\\ 3x+7=0\end{array}\right.\iff \left[\begin{array}{l}x=-3\\ x=-\frac{7}{3}\end{array}\right.\end{array}$