8u^2+18u-5=0

Solution for 8u^2+18u-5=0 equation:

Simplifying
8u2 + 18u + -5 = 0

Reorder the terms:
-5 + 18u + 8u2 = 0

Solving
-5 + 18u + 8u2 = 0

Solving for variable 'u'.

Factor a trinomial.
(-5 + -2u)(1 + -4u) = 0

Subproblem 1
Set the factor '(-5 + -2u)' equal to zero and attempt to solve:

Simplifying
-5 + -2u = 0

Solving
-5 + -2u = 0

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

Add '5' to each side of the equation.
-5 + 5 + -2u = 0 + 5

Combine like terms: -5 + 5 = 0
0 + -2u = 0 + 5
-2u = 0 + 5

Combine like terms: 0 + 5 = 5
-2u = 5

Divide each side by '-2'.
u = -2.5

Simplifying
u = -2.5
Subproblem 2
Set the factor '(1 + -4u)' equal to zero and attempt to solve:

Simplifying
1 + -4u = 0

Solving
1 + -4u = 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 + -4u = 0 + -1

Combine like terms: 1 + -1 = 0
0 + -4u = 0 + -1
-4u = 0 + -1

Combine like terms: 0 + -1 = -1
-4u = -1

Divide each side by '-4'.
u = 0.25

Simplifying
u = 0.25
Solution
u = {-2.5, 0.25}