9b+21b^2-30=0

Solution for 9b+21b^2-30=0 equation:

Simplifying
9b + 21b2 + -30 = 0

Reorder the terms:
-30 + 9b + 21b2 = 0

Solving
-30 + 9b + 21b2 = 0

Solving for variable 'b'.

Factor out the Greatest Common Factor (GCF), '3'.
3(-10 + 3b + 7b2) = 0

Factor a trinomial.
3((-10 + -7b)(1 + -1b)) = 0

Ignore the factor 3.
Subproblem 1
Set the factor '(-10 + -7b)' equal to zero and attempt to solve:

Simplifying
-10 + -7b = 0

Solving
-10 + -7b = 0

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

Add '10' to each side of the equation.
-10 + 10 + -7b = 0 + 10

Combine like terms: -10 + 10 = 0
0 + -7b = 0 + 10
-7b = 0 + 10

Combine like terms: 0 + 10 = 10
-7b = 10

Divide each side by '-7'.
b = -1.428571429

Simplifying
b = -1.428571429
Subproblem 2
Set the factor '(1 + -1b)' equal to zero and attempt to solve:

Simplifying
1 + -1b = 0

Solving
1 + -1b = 0

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

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

Combine like terms: 1 + -1 = 0
0 + -1b = 0 + -1
-1b = 0 + -1

Combine like terms: 0 + -1 = -1
-1b = -1

Divide each side by '-1'.
b = 1

Simplifying
b = 1
Solution
b = {-1.428571429, 1}