(f-5)(f+5)=

Solution for (f-5)(f+5)= equation:

Simplifying
(f + -5)(f + 5) = 0

Reorder the terms:
(-5 + f)(f + 5) = 0

Reorder the terms:
(-5 + f)(5 + f) = 0

Multiply (-5 + f) * (5 + f)
(-5(5 + f) + f(5 + f)) = 0
((5 * -5 + f * -5) + f(5 + f)) = 0
((-25 + -5f) + f(5 + f)) = 0
(-25 + -5f + (5 * f + f * f)) = 0
(-25 + -5f + (5f + f2)) = 0

Combine like terms: -5f + 5f = 0
(-25 + 0 + f2) = 0
(-25 + f2) = 0

Solving
-25 + f2 = 0

Solving for variable 'f'.

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

Add '25' to each side of the equation.
-25 + 25 + f2 = 0 + 25

Combine like terms: -25 + 25 = 0
0 + f2 = 0 + 25
f2 = 0 + 25

Combine like terms: 0 + 25 = 25
f2 = 25

Simplifying
f2 = 25

Take the square root of each side:
f = {-5, 5}