(ab+4)(ab-4)=

Solution for (ab+4)(ab-4)= equation:

Simplifying
(ab + 4)(ab + -4) = 0

Reorder the terms:
(4 + ab)(ab + -4) = 0

Reorder the terms:
(4 + ab)(-4 + ab) = 0

Multiply (4 + ab) * (-4 + ab)
(4(-4 + ab) + ab(-4 + ab)) = 0
((-4 * 4 + ab * 4) + ab(-4 + ab)) = 0
((-16 + 4ab) + ab(-4 + ab)) = 0
(-16 + 4ab + (-4 * ab + ab * ab)) = 0
(-16 + 4ab + (-4ab + a2b2)) = 0

Combine like terms: 4ab + -4ab = 0
(-16 + 0 + a2b2) = 0
(-16 + a2b2) = 0

Solving
-16 + a2b2 = 0

Solving for variable 'a'.

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

Add '16' to each side of the equation.
-16 + 16 + a2b2 = 0 + 16

Combine like terms: -16 + 16 = 0
0 + a2b2 = 0 + 16
a2b2 = 0 + 16

Combine like terms: 0 + 16 = 16
a2b2 = 16

Divide each side by 'b2'.
a2 = 16b-2

Simplifying
a2 = 16b-2

Take the square root of each side:
a = {-4b-1, 4b-1}