-2a^2+9=0

Solution for -2a^2+9=0 equation:

Simplifying
-2a2 + 9 = 0

Reorder the terms:
9 + -2a2 = 0

Solving
9 + -2a2 = 0

Solving for variable 'a'.

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

Add '-9' to each side of the equation.
9 + -9 + -2a2 = 0 + -9

Combine like terms: 9 + -9 = 0
0 + -2a2 = 0 + -9
-2a2 = 0 + -9

Combine like terms: 0 + -9 = -9
-2a2 = -9

Divide each side by '-2'.
a2 = 4.5

Simplifying
a2 = 4.5

Take the square root of each side:
a = {-2.121320344, 2.121320344}