Question

Answer 1

\(7x\left(x-8\right)+14\left(x-8\right)=0\)

\(\left[{}\begin{matrix}7x+14=0\\x-8=0\end{matrix}\right.\)\(\Leftrightarrow\left[{}\begin{matrix}x=-2\\x=8\end{matrix}\right.\)

Answer 2

a) \(7x\left(x-8\right)-14\left(x-8\right)=0\)

\(\Rightarrow7\left(x-8\right)\left(x-2\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=8\\x=2\end{matrix}\right.\)

b) \(\left(x+1\right)\left(x-3\right)-x\left(x-4\right)=7\)

\(\Rightarrow x^2-2x-3-x^2+4x=7\)

\(\Rightarrow2x=10\Rightarrow x=5\)