Question

x(x+1)-x(x-3)=0 x²+7x-8=0

Answer 1

\(a,\Rightarrow x\left(x+1-x+3\right)=0\\ \Rightarrow x=0\\ b,\Rightarrow x^2-x+8x-8=0\\ \Rightarrow\left(x-1\right)\left(x+8\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=1\\x=-8\end{matrix}\right.\)

Answer 2

1) \(x\left(x+1\right)-x\left(x-3\right)=0\)

\(\Rightarrow x^2+x-x^2+3x=0\Rightarrow4x=0\Rightarrow x=0\)

2) \(x^2+7x-8=0\Rightarrow x\left(x-1\right)+8\left(x-1\right)=0\)

\(\Rightarrow\left(x-1\right)\left(x+8\right)=0\)\(\Rightarrow\left[{}\begin{matrix}x=1\\x=-8\end{matrix}\right.\)