4d^2-20d+9=0

Solution for 4d^2-20d+9=0 equation:

Simplifying
4d2 + -20d + 9 = 0

Reorder the terms:
9 + -20d + 4d2 = 0

Solving
9 + -20d + 4d2 = 0

Solving for variable 'd'.

Factor a trinomial.
(1 + -2d)(9 + -2d) = 0

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

Simplifying
1 + -2d = 0

Solving
1 + -2d = 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 + -2d = 0 + -1

Combine like terms: 1 + -1 = 0
0 + -2d = 0 + -1
-2d = 0 + -1

Combine like terms: 0 + -1 = -1
-2d = -1

Divide each side by '-2'.
d = 0.5

Simplifying
d = 0.5
Subproblem 2
Set the factor '(9 + -2d)' equal to zero and attempt to solve:

Simplifying
9 + -2d = 0

Solving
9 + -2d = 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 + -2d = 0 + -9

Combine like terms: 9 + -9 = 0
0 + -2d = 0 + -9
-2d = 0 + -9

Combine like terms: 0 + -9 = -9
-2d = -9

Divide each side by '-2'.
d = 4.5

Simplifying
d = 4.5
Solution
d = {0.5, 4.5}