15-b-9+6b=30

Solution for 15-b-9+6b=30 equation:

Simplifying
15 + -1b + -9 + 6b = 30

Reorder the terms:
15 + -9 + -1b + 6b = 30

Combine like terms: 15 + -9 = 6
6 + -1b + 6b = 30

Combine like terms: -1b + 6b = 5b
6 + 5b = 30

Solving
6 + 5b = 30

Solving for variable 'b'.

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

Add '-6' to each side of the equation.
6 + -6 + 5b = 30 + -6

Combine like terms: 6 + -6 = 0
0 + 5b = 30 + -6
5b = 30 + -6

Combine like terms: 30 + -6 = 24
5b = 24

Divide each side by '5'.
b = 4.8

Simplifying
b = 4.8