(2d-2)(9d+9)=

Solution for (2d-2)(9d+9)= equation:

Simplifying
(2d + -2)(9d + 9) = 0

Reorder the terms:
(-2 + 2d)(9d + 9) = 0

Reorder the terms:
(-2 + 2d)(9 + 9d) = 0

Multiply (-2 + 2d) * (9 + 9d)
(-2(9 + 9d) + 2d * (9 + 9d)) = 0
((9 * -2 + 9d * -2) + 2d * (9 + 9d)) = 0
((-18 + -18d) + 2d * (9 + 9d)) = 0
(-18 + -18d + (9 * 2d + 9d * 2d)) = 0
(-18 + -18d + (18d + 18d2)) = 0

Combine like terms: -18d + 18d = 0
(-18 + 0 + 18d2) = 0
(-18 + 18d2) = 0

Solving
-18 + 18d2 = 0

Solving for variable 'd'.

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

Add '18' to each side of the equation.
-18 + 18 + 18d2 = 0 + 18

Combine like terms: -18 + 18 = 0
0 + 18d2 = 0 + 18
18d2 = 0 + 18

Combine like terms: 0 + 18 = 18
18d2 = 18

Divide each side by '18'.
d2 = 1

Simplifying
d2 = 1

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