9p^2-3p-21=-1

Solution for 9p^2-3p-21=-1 equation:

Simplifying
9p2 + -3p + -21 = -1

Reorder the terms:
-21 + -3p + 9p2 = -1

Solving
-21 + -3p + 9p2 = -1

Solving for variable 'p'.

Reorder the terms:
-21 + 1 + -3p + 9p2 = -1 + 1

Combine like terms: -21 + 1 = -20
-20 + -3p + 9p2 = -1 + 1

Combine like terms: -1 + 1 = 0
-20 + -3p + 9p2 = 0

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

Subproblem 1
Set the factor '(-4 + -3p)' equal to zero and attempt to solve:

Simplifying
-4 + -3p = 0

Solving
-4 + -3p = 0

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

Add '4' to each side of the equation.
-4 + 4 + -3p = 0 + 4

Combine like terms: -4 + 4 = 0
0 + -3p = 0 + 4
-3p = 0 + 4

Combine like terms: 0 + 4 = 4
-3p = 4

Divide each side by '-3'.
p = -1.333333333

Simplifying
p = -1.333333333
Subproblem 2
Set the factor '(5 + -3p)' equal to zero and attempt to solve:

Simplifying
5 + -3p = 0

Solving
5 + -3p = 0

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

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

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

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

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

Simplifying
p = 1.666666667
Solution
p = {-1.333333333, 1.666666667}