8t^2-2t-15=0

Solution for 8t^2-2t-15=0 equation:

Simplifying
8t2 + -2t + -15 = 0

Reorder the terms:
-15 + -2t + 8t2 = 0

Solving
-15 + -2t + 8t2 = 0

Solving for variable 't'.

Factor a trinomial.
(-5 + -4t)(3 + -2t) = 0

Subproblem 1
Set the factor '(-5 + -4t)' equal to zero and attempt to solve:

Simplifying
-5 + -4t = 0

Solving
-5 + -4t = 0

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

Add '5' to each side of the equation.
-5 + 5 + -4t = 0 + 5

Combine like terms: -5 + 5 = 0
0 + -4t = 0 + 5
-4t = 0 + 5

Combine like terms: 0 + 5 = 5
-4t = 5

Divide each side by '-4'.
t = -1.25

Simplifying
t = -1.25
Subproblem 2
Set the factor '(3 + -2t)' equal to zero and attempt to solve:

Simplifying
3 + -2t = 0

Solving
3 + -2t = 0

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

Add '-3' to each side of the equation.
3 + -3 + -2t = 0 + -3

Combine like terms: 3 + -3 = 0
0 + -2t = 0 + -3
-2t = 0 + -3

Combine like terms: 0 + -3 = -3
-2t = -3

Divide each side by '-2'.
t = 1.5

Simplifying
t = 1.5
Solution
t = {-1.25, 1.5}