8z^2+20z-72=

Solution for 8z^2+20z-72= equation:

Simplifying
8z2 + 20z + -72 = 0

Reorder the terms:
-72 + 20z + 8z2 = 0

Solving
-72 + 20z + 8z2 = 0

Solving for variable 'z'.

Factor out the Greatest Common Factor (GCF), '4'.
4(-18 + 5z + 2z2) = 0

Factor a trinomial.
4((-9 + -2z)(2 + -1z)) = 0

Ignore the factor 4.
Subproblem 1
Set the factor '(-9 + -2z)' equal to zero and attempt to solve:

Simplifying
-9 + -2z = 0

Solving
-9 + -2z = 0

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

Add '9' to each side of the equation.
-9 + 9 + -2z = 0 + 9

Combine like terms: -9 + 9 = 0
0 + -2z = 0 + 9
-2z = 0 + 9

Combine like terms: 0 + 9 = 9
-2z = 9

Divide each side by '-2'.
z = -4.5

Simplifying
z = -4.5
Subproblem 2
Set the factor '(2 + -1z)' equal to zero and attempt to solve:

Simplifying
2 + -1z = 0

Solving
2 + -1z = 0

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

Add '-2' to each side of the equation.
2 + -2 + -1z = 0 + -2

Combine like terms: 2 + -2 = 0
0 + -1z = 0 + -2
-1z = 0 + -2

Combine like terms: 0 + -2 = -2
-1z = -2

Divide each side by '-1'.
z = 2

Simplifying
z = 2
Solution
z = {-4.5, 2}