15z^2-16z-15=

Solution for 15z^2-16z-15= equation:

Simplifying
15z2 + -16z + -15 = 0

Reorder the terms:
-15 + -16z + 15z2 = 0

Solving
-15 + -16z + 15z2 = 0

Solving for variable 'z'.

Factor a trinomial.
(-3 + -5z)(5 + -3z) = 0

Subproblem 1
Set the factor '(-3 + -5z)' equal to zero and attempt to solve:

Simplifying
-3 + -5z = 0

Solving
-3 + -5z = 0

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

Add '3' to each side of the equation.
-3 + 3 + -5z = 0 + 3

Combine like terms: -3 + 3 = 0
0 + -5z = 0 + 3
-5z = 0 + 3

Combine like terms: 0 + 3 = 3
-5z = 3

Divide each side by '-5'.
z = -0.6

Simplifying
z = -0.6
Subproblem 2
Set the factor '(5 + -3z)' equal to zero and attempt to solve:

Simplifying
5 + -3z = 0

Solving
5 + -3z = 0

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

Add '-5' to each side of the equation.
5 + -5 + -3z = 0 + -5

Combine like terms: 5 + -5 = 0
0 + -3z = 0 + -5
-3z = 0 + -5

Combine like terms: 0 + -5 = -5
-3z = -5

Divide each side by '-3'.
z = 1.666666667

Simplifying
z = 1.666666667
Solution
z = {-0.6, 1.666666667}