2x^2-1-7=0

Solution for 2x^2-1-7=0 equation:

Simplifying
2x2 + -1 + -7 = 0

Reorder the terms:
-1 + -7 + 2x2 = 0

Combine like terms: -1 + -7 = -8
-8 + 2x2 = 0

Solving
-8 + 2x2 = 0

Solving for variable 'x'.

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

Add '8' to each side of the equation.
-8 + 8 + 2x2 = 0 + 8

Combine like terms: -8 + 8 = 0
0 + 2x2 = 0 + 8
2x2 = 0 + 8

Combine like terms: 0 + 8 = 8
2x2 = 8

Divide each side by '2'.
x2 = 4

Simplifying
x2 = 4

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