Factor \({x}^{2}+8x-9\).
Ask: Which two numbers add up to \(8\) and multiply to \(-9\)?
Rewrite the expression using the above.
\[(x-1)(x+9)\]
Solve for \(x\).
Ask: When will \((x-1)(x+9)\) equal zero?
When \(x-1=0\) or \(x+9=0\)
Solve each of the 2 equations above.
\[x=1,-9\]
