(2a+5)(2a-5)=

Solution for (2a+5)(2a-5)= equation:

Simplifying
(2a + 5)(2a + -5) = 0

Reorder the terms:
(5 + 2a)(2a + -5) = 0

Reorder the terms:
(5 + 2a)(-5 + 2a) = 0

Multiply (5 + 2a) * (-5 + 2a)
(5(-5 + 2a) + 2a * (-5 + 2a)) = 0
((-5 * 5 + 2a * 5) + 2a * (-5 + 2a)) = 0
((-25 + 10a) + 2a * (-5 + 2a)) = 0
(-25 + 10a + (-5 * 2a + 2a * 2a)) = 0
(-25 + 10a + (-10a + 4a2)) = 0

Combine like terms: 10a + -10a = 0
(-25 + 0 + 4a2) = 0
(-25 + 4a2) = 0

Solving
-25 + 4a2 = 0

Solving for variable 'a'.

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

Add '25' to each side of the equation.
-25 + 25 + 4a2 = 0 + 25

Combine like terms: -25 + 25 = 0
0 + 4a2 = 0 + 25
4a2 = 0 + 25

Combine like terms: 0 + 25 = 25
4a2 = 25

Divide each side by '4'.
a2 = 6.25

Simplifying
a2 = 6.25

Take the square root of each side:
a = {-2.5, 2.5}