Question

x2 – 25   –  7(x – 5) = 0 Tìm x

Answer 1

\(x^2-25-7\left(x-5\right)=0\)

\(\Rightarrow\left(x-5\right)\left(x+5\right)-7\left(x-5\right)=0\)

\(\Rightarrow\left(x-5\right)\left(x-2\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=5\\x=2\end{matrix}\right.\)