d^2=10d-9

Solution for d^2=10d-9 equation:

Simplifying
d2 = 10d + -9

Reorder the terms:
d2 = -9 + 10d

Solving
d2 = -9 + 10d

Solving for variable 'd'.

Reorder the terms:
9 + -10d + d2 = -9 + 10d + 9 + -10d

Reorder the terms:
9 + -10d + d2 = -9 + 9 + 10d + -10d

Combine like terms: -9 + 9 = 0
9 + -10d + d2 = 0 + 10d + -10d
9 + -10d + d2 = 10d + -10d

Combine like terms: 10d + -10d = 0
9 + -10d + d2 = 0

Factor a trinomial.
(1 + -1d)(9 + -1d) = 0

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 '(9 + -1d)' equal to zero and attempt to solve:

Simplifying
9 + -1d = 0

Solving
9 + -1d = 0

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

Add '-9' to each side of the equation.
9 + -9 + -1d = 0 + -9

Combine like terms: 9 + -9 = 0
0 + -1d = 0 + -9
-1d = 0 + -9

Combine like terms: 0 + -9 = -9
-1d = -9

Divide each side by '-1'.
d = 9

Simplifying
d = 9
Solution
d = {1, 9}