(a-10)(a+10)=

Solution for (a-10)(a+10)= equation:

Simplifying
(a + -10)(a + 10) = 0

Reorder the terms:
(-10 + a)(a + 10) = 0

Reorder the terms:
(-10 + a)(10 + a) = 0

Multiply (-10 + a) * (10 + a)
(-10(10 + a) + a(10 + a)) = 0
((10 * -10 + a * -10) + a(10 + a)) = 0
((-100 + -10a) + a(10 + a)) = 0
(-100 + -10a + (10 * a + a * a)) = 0
(-100 + -10a + (10a + a2)) = 0

Combine like terms: -10a + 10a = 0
(-100 + 0 + a2) = 0
(-100 + a2) = 0

Solving
-100 + a2 = 0

Solving for variable 'a'.

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

Add '100' to each side of the equation.
-100 + 100 + a2 = 0 + 100

Combine like terms: -100 + 100 = 0
0 + a2 = 0 + 100
a2 = 0 + 100

Combine like terms: 0 + 100 = 100
a2 = 100

Simplifying
a2 = 100

Take the square root of each side:
a = {-10, 10}