91z+30z^2-30=

Solution for 91z+30z^2-30= equation:

Simplifying
91z + 30z2 + -30 = 0

Reorder the terms:
-30 + 91z + 30z2 = 0

Solving
-30 + 91z + 30z2 = 0

Solving for variable 'z'.

Factor a trinomial.
(-10 + -3z)(3 + -10z) = 0

Subproblem 1
Set the factor '(-10 + -3z)' equal to zero and attempt to solve:

Simplifying
-10 + -3z = 0

Solving
-10 + -3z = 0

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

Add '10' to each side of the equation.
-10 + 10 + -3z = 0 + 10

Combine like terms: -10 + 10 = 0
0 + -3z = 0 + 10
-3z = 0 + 10

Combine like terms: 0 + 10 = 10
-3z = 10

Divide each side by '-3'.
z = -3.333333333

Simplifying
z = -3.333333333
Subproblem 2
Set the factor '(3 + -10z)' equal to zero and attempt to solve:

Simplifying
3 + -10z = 0

Solving
3 + -10z = 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 + -10z = 0 + -3

Combine like terms: 3 + -3 = 0
0 + -10z = 0 + -3
-10z = 0 + -3

Combine like terms: 0 + -3 = -3
-10z = -3

Divide each side by '-10'.
z = 0.3

Simplifying
z = 0.3
Solution
z = {-3.333333333, 0.3}