91=h(2h-1)

Solution for 91=h(2h-1) equation:

Simplifying
91 = h(2h + -1)

Reorder the terms:
91 = h(-1 + 2h)
91 = (-1 * h + 2h * h)
91 = (-1h + 2h2)

Solving
91 = -1h + 2h2

Solving for variable 'h'.

Reorder the terms:
91 + h + -2h2 = -1h + h + 2h2 + -2h2

Combine like terms: -1h + h = 0
91 + h + -2h2 = 0 + 2h2 + -2h2
91 + h + -2h2 = 2h2 + -2h2

Combine like terms: 2h2 + -2h2 = 0
91 + h + -2h2 = 0

Factor a trinomial.
(7 + -1h)(13 + 2h) = 0

Subproblem 1
Set the factor '(7 + -1h)' equal to zero and attempt to solve:

Simplifying
7 + -1h = 0

Solving
7 + -1h = 0

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

Add '-7' to each side of the equation.
7 + -7 + -1h = 0 + -7

Combine like terms: 7 + -7 = 0
0 + -1h = 0 + -7
-1h = 0 + -7

Combine like terms: 0 + -7 = -7
-1h = -7

Divide each side by '-1'.
h = 7

Simplifying
h = 7
Subproblem 2
Set the factor '(13 + 2h)' equal to zero and attempt to solve:

Simplifying
13 + 2h = 0

Solving
13 + 2h = 0

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

Add '-13' to each side of the equation.
13 + -13 + 2h = 0 + -13

Combine like terms: 13 + -13 = 0
0 + 2h = 0 + -13
2h = 0 + -13

Combine like terms: 0 + -13 = -13
2h = -13

Divide each side by '2'.
h = -6.5

Simplifying
h = -6.5
Solution
h = {7, -6.5}