-3(1-3b)+7b=-131

Solution for -3(1-3b)+7b=-131 equation:

Simplifying
-3(1 + -3b) + 7b = -131
(1 * -3 + -3b * -3) + 7b = -131
(-3 + 9b) + 7b = -131

Combine like terms: 9b + 7b = 16b
-3 + 16b = -131

Solving
-3 + 16b = -131

Solving for variable 'b'.

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

Add '3' to each side of the equation.
-3 + 3 + 16b = -131 + 3

Combine like terms: -3 + 3 = 0
0 + 16b = -131 + 3
16b = -131 + 3

Combine like terms: -131 + 3 = -128
16b = -128

Divide each side by '16'.
b = -8

Simplifying
b = -8