70=5t^2-15t-20

Solution for 70=5t^2-15t-20 equation:

Simplifying
70 = 5t2 + -15t + -20

Reorder the terms:
70 = -20 + -15t + 5t2

Solving
70 = -20 + -15t + 5t2

Solving for variable 't'.

Combine like terms: 70 + 20 = 90
90 + 15t + -5t2 = -20 + -15t + 5t2 + 20 + 15t + -5t2

Reorder the terms:
90 + 15t + -5t2 = -20 + 20 + -15t + 15t + 5t2 + -5t2

Combine like terms: -20 + 20 = 0
90 + 15t + -5t2 = 0 + -15t + 15t + 5t2 + -5t2
90 + 15t + -5t2 = -15t + 15t + 5t2 + -5t2

Combine like terms: -15t + 15t = 0
90 + 15t + -5t2 = 0 + 5t2 + -5t2
90 + 15t + -5t2 = 5t2 + -5t2

Combine like terms: 5t2 + -5t2 = 0
90 + 15t + -5t2 = 0

Factor out the Greatest Common Factor (GCF), '5'.
5(18 + 3t + -1t2) = 0

Factor a trinomial.
5((6 + -1t)(3 + t)) = 0

Ignore the factor 5.
Subproblem 1
Set the factor '(6 + -1t)' equal to zero and attempt to solve:

Simplifying
6 + -1t = 0

Solving
6 + -1t = 0

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

Add '-6' to each side of the equation.
6 + -6 + -1t = 0 + -6

Combine like terms: 6 + -6 = 0
0 + -1t = 0 + -6
-1t = 0 + -6

Combine like terms: 0 + -6 = -6
-1t = -6

Divide each side by '-1'.
t = 6

Simplifying
t = 6
Subproblem 2
Set the factor '(3 + t)' equal to zero and attempt to solve:

Simplifying
3 + t = 0

Solving
3 + t = 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 + t = 0 + -3

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

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

Simplifying
t = -3
Solution
t = {6, -3}