2x^2-39=90

Solution for 2x^2-39=90 equation:

Simplifying
2x2 + -39 = 90

Reorder the terms:
-39 + 2x2 = 90

Solving
-39 + 2x2 = 90

Solving for variable 'x'.

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

Add '39' to each side of the equation.
-39 + 39 + 2x2 = 90 + 39

Combine like terms: -39 + 39 = 0
0 + 2x2 = 90 + 39
2x2 = 90 + 39

Combine like terms: 90 + 39 = 129
2x2 = 129

Divide each side by '2'.
x2 = 64.5

Simplifying
x2 = 64.5

Take the square root of each side:
x = {-8.031189202, 8.031189202}