Question

15 points and show steps

Answer 1

Answer:

x = -7 and x = 7

Step-by-step explanation:

$-2x^2-9=-107\qquad\text{add 9 to both sides}\\\\-2x^2-9+9=-107+9\\\\-2x^2=-98\qquad\text{divide both sides by (-2)}\\\\\dfrac{-2x^2}{-2}=\dfrac{-98}{-2}\\\\x^2=49\to x=\pm\sqrt{49}\\\\x=-7\ \vee\ x=7$