15=b-7b

Solution for 15=b-7b equation:

Simplifying
15 = b + -7b

Combine like terms: b + -7b = -6b
15 = -6b

Solving
15 = -6b

Solving for variable 'b'.

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

Add '6b' to each side of the equation.
15 + 6b = -6b + 6b

Combine like terms: -6b + 6b = 0
15 + 6b = 0

Add '-15' to each side of the equation.
15 + -15 + 6b = 0 + -15

Combine like terms: 15 + -15 = 0
0 + 6b = 0 + -15
6b = 0 + -15

Combine like terms: 0 + -15 = -15
6b = -15

Divide each side by '6'.
b = -2.5

Simplifying
b = -2.5