(8r-5)(8r+5)=

Solution for (8r-5)(8r+5)= equation:

Simplifying
(8r + -5)(8r + 5) = 0

Reorder the terms:
(-5 + 8r)(8r + 5) = 0

Reorder the terms:
(-5 + 8r)(5 + 8r) = 0

Multiply (-5 + 8r) * (5 + 8r)
(-5(5 + 8r) + 8r * (5 + 8r)) = 0
((5 * -5 + 8r * -5) + 8r * (5 + 8r)) = 0
((-25 + -40r) + 8r * (5 + 8r)) = 0
(-25 + -40r + (5 * 8r + 8r * 8r)) = 0
(-25 + -40r + (40r + 64r2)) = 0

Combine like terms: -40r + 40r = 0
(-25 + 0 + 64r2) = 0
(-25 + 64r2) = 0

Solving
-25 + 64r2 = 0

Solving for variable 'r'.

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

Add '25' to each side of the equation.
-25 + 25 + 64r2 = 0 + 25

Combine like terms: -25 + 25 = 0
0 + 64r2 = 0 + 25
64r2 = 0 + 25

Combine like terms: 0 + 25 = 25
64r2 = 25

Divide each side by '64'.
r2 = 0.390625

Simplifying
r2 = 0.390625

Take the square root of each side:
r = {-0.625, 0.625}