-4x^2-15=-31

Solution for -4x^2-15=-31 equation:

Simplifying
-4x2 + -15 = -31

Reorder the terms:
-15 + -4x2 = -31

Solving
-15 + -4x2 = -31

Solving for variable 'x'.

Move all terms containing x to the left, all other terms to the right.

Add '15' to each side of the equation.
-15 + 15 + -4x2 = -31 + 15

Combine like terms: -15 + 15 = 0
0 + -4x2 = -31 + 15
-4x2 = -31 + 15

Combine like terms: -31 + 15 = -16
-4x2 = -16

Divide each side by '-4'.
x2 = 4

Simplifying
x2 = 4

Take the square root of each side:
x = {-2, 2}