Question

Answer 1

a: Ta có: \(5\left(x+3\right)-2x\left(x+3\right)=0\)

\(\Leftrightarrow\left(x+3\right)\left(2x-5\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=-3\\x=\dfrac{5}{2}\end{matrix}\right.\)

c: Ta có: \(\left(x+4\right)^2-16=0\)

\(\Leftrightarrow x\left(x+8\right)=0\)

\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-8\end{matrix}\right.\)

Answer 2

d)\(x^2-10x=-25\)

\(x^2-10x+25=0\)

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

\(\Rightarrow x-5=0\)

\(\Leftrightarrow x=5\)

Vậy........