8u^2-71u=9

Solution for 8u^2-71u=9 equation:

Simplifying
8u2 + -71u = 9

Reorder the terms:
-71u + 8u2 = 9

Solving
-71u + 8u2 = 9

Solving for variable 'u'.

Reorder the terms:
-9 + -71u + 8u2 = 9 + -9

Combine like terms: 9 + -9 = 0
-9 + -71u + 8u2 = 0

Factor a trinomial.
(-1 + -8u)(9 + -1u) = 0

Subproblem 1
Set the factor '(-1 + -8u)' equal to zero and attempt to solve:

Simplifying
-1 + -8u = 0

Solving
-1 + -8u = 0

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

Add '1' to each side of the equation.
-1 + 1 + -8u = 0 + 1

Combine like terms: -1 + 1 = 0
0 + -8u = 0 + 1
-8u = 0 + 1

Combine like terms: 0 + 1 = 1
-8u = 1

Divide each side by '-8'.
u = -0.125

Simplifying
u = -0.125
Subproblem 2
Set the factor '(9 + -1u)' equal to zero and attempt to solve:

Simplifying
9 + -1u = 0

Solving
9 + -1u = 0

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

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

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

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

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

Simplifying
u = 9
Solution
u = {-0.125, 9}