Solve $LaTeX: \displaystyle - 2 x^{2} - 4 x + 160=0$

Since the GCF is $LaTeX: \displaystyle -2$ we need we factor out the GCF to get $LaTeX: \displaystyle -2(x^{2} + 2 x - 80)$ . This is now a pq method factoring. The factors of $LaTeX: \displaystyle -80$ that add up to $LaTeX: \displaystyle 2$ are $LaTeX: \displaystyle -8$ and $LaTeX: \displaystyle 10$ . This gives $LaTeX: \displaystyle -2(x - 8)(x + 10)=0$ . The solutions are $LaTeX: \displaystyle x = 8$ and $LaTeX: \displaystyle x = -10$