(2y+5)(2y-5)=12

Solution for (2y+5)(2y-5)=12 equation:

Simplifying
(2y + 5)(2y + -5) = 12

Reorder the terms:
(5 + 2y)(2y + -5) = 12

Reorder the terms:
(5 + 2y)(-5 + 2y) = 12

Multiply (5 + 2y) * (-5 + 2y)
(5(-5 + 2y) + 2y * (-5 + 2y)) = 12
((-5 * 5 + 2y * 5) + 2y * (-5 + 2y)) = 12
((-25 + 10y) + 2y * (-5 + 2y)) = 12
(-25 + 10y + (-5 * 2y + 2y * 2y)) = 12
(-25 + 10y + (-10y + 4y2)) = 12

Combine like terms: 10y + -10y = 0
(-25 + 0 + 4y2) = 12
(-25 + 4y2) = 12

Solving
-25 + 4y2 = 12

Solving for variable 'y'.

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

Add '25' to each side of the equation.
-25 + 25 + 4y2 = 12 + 25

Combine like terms: -25 + 25 = 0
0 + 4y2 = 12 + 25
4y2 = 12 + 25

Combine like terms: 12 + 25 = 37
4y2 = 37

Divide each side by '4'.
y2 = 9.25

Simplifying
y2 = 9.25

Take the square root of each side:
y = {-3.041381265, 3.041381265}