81y^2-36=0

Solution for 81y^2-36=0 equation:

Simplifying
81y2 + -36 = 0

Reorder the terms:
-36 + 81y2 = 0

Solving
-36 + 81y2 = 0

Solving for variable 'y'.

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

Add '36' to each side of the equation.
-36 + 36 + 81y2 = 0 + 36

Combine like terms: -36 + 36 = 0
0 + 81y2 = 0 + 36
81y2 = 0 + 36

Combine like terms: 0 + 36 = 36
81y2 = 36

Divide each side by '81'.
y2 = 0.4444444444

Simplifying
y2 = 0.4444444444

Take the square root of each side:
y = {-0.666666667, 0.666666667}