Factor \({x}^{2}+7x+12\).
Ask: Which two numbers add up to \(7\) and multiply to \(12\)?
Rewrite the expression using the above.
\[(x+3)(x+4)\]
\[(x+3)(x+4)({x}^{2}-8x+15)=0\]
Factor \({x}^{2}-8x+15\).
Ask: Which two numbers add up to \(-8\) and multiply to \(15\)?
Rewrite the expression using the above.
\[(x-5)(x-3)\]
\[(x+3)(x+4)(x-5)(x-3)=0\]
Solve for \(x\).
Ask: When will \((x+3)(x+4)(x-5)(x-3)\) equal zero?
When \(x+3=0\), \(x+4=0\), \(x-5=0\), or \(x-3=0\)
Solve each of the 4 equations above.
\[x=-4,5,\pm 3\]
\[x=-4,5,\pm 3\]
x=-3,-4,5,3
