(4a-4)(a+1)=

Solution for (4a-4)(a+1)= equation:

Simplifying
(4a + -4)(a + 1) = 0

Reorder the terms:
(-4 + 4a)(a + 1) = 0

Reorder the terms:
(-4 + 4a)(1 + a) = 0

Multiply (-4 + 4a) * (1 + a)
(-4(1 + a) + 4a * (1 + a)) = 0
((1 * -4 + a * -4) + 4a * (1 + a)) = 0
((-4 + -4a) + 4a * (1 + a)) = 0
(-4 + -4a + (1 * 4a + a * 4a)) = 0
(-4 + -4a + (4a + 4a2)) = 0

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

Solving
-4 + 4a2 = 0

Solving for variable 'a'.

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

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

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

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

Divide each side by '4'.
a2 = 1

Simplifying
a2 = 1

Take the square root of each side:
a = {-1, 1}