(2d-6)(5d+5)=0

Solution for (2d-6)(5d+5)=0 equation:

Simplifying
(2d + -6)(5d + 5) = 0

Reorder the terms:
(-6 + 2d)(5d + 5) = 0

Reorder the terms:
(-6 + 2d)(5 + 5d) = 0

Multiply (-6 + 2d) * (5 + 5d)
(-6(5 + 5d) + 2d * (5 + 5d)) = 0
((5 * -6 + 5d * -6) + 2d * (5 + 5d)) = 0
((-30 + -30d) + 2d * (5 + 5d)) = 0
(-30 + -30d + (5 * 2d + 5d * 2d)) = 0
(-30 + -30d + (10d + 10d2)) = 0

Combine like terms: -30d + 10d = -20d
(-30 + -20d + 10d2) = 0

Solving
-30 + -20d + 10d2 = 0

Solving for variable 'd'.

Factor out the Greatest Common Factor (GCF), '10'.
10(-3 + -2d + d2) = 0

Factor a trinomial.
10((-1 + -1d)(3 + -1d)) = 0

Ignore the factor 10.
Subproblem 1
Set the factor '(-1 + -1d)' equal to zero and attempt to solve:

Simplifying
-1 + -1d = 0

Solving
-1 + -1d = 0

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

Add '1' to each side of the equation.
-1 + 1 + -1d = 0 + 1

Combine like terms: -1 + 1 = 0
0 + -1d = 0 + 1
-1d = 0 + 1

Combine like terms: 0 + 1 = 1
-1d = 1

Divide each side by '-1'.
d = -1

Simplifying
d = -1
Subproblem 2
Set the factor '(3 + -1d)' equal to zero and attempt to solve:

Simplifying
3 + -1d = 0

Solving
3 + -1d = 0

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

Add '-3' to each side of the equation.
3 + -3 + -1d = 0 + -3

Combine like terms: 3 + -3 = 0
0 + -1d = 0 + -3
-1d = 0 + -3

Combine like terms: 0 + -3 = -3
-1d = -3

Divide each side by '-1'.
d = 3

Simplifying
d = 3
Solution
d = {-1, 3}