b-4(b-3(1-b))=42

Solution for b-4(b-3(1-b))=42 equation:

Simplifying
b + -4(b + -3(1 + -1b)) = 42
b + -4(b + (1 * -3 + -1b * -3)) = 42
b + -4(b + (-3 + 3b)) = 42

Reorder the terms:
b + -4(-3 + b + 3b) = 42

Combine like terms: b + 3b = 4b
b + -4(-3 + 4b) = 42
b + (-3 * -4 + 4b * -4) = 42
b + (12 + -16b) = 42

Reorder the terms:
12 + b + -16b = 42

Combine like terms: b + -16b = -15b
12 + -15b = 42

Solving
12 + -15b = 42

Solving for variable 'b'.

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

Add '-12' to each side of the equation.
12 + -12 + -15b = 42 + -12

Combine like terms: 12 + -12 = 0
0 + -15b = 42 + -12
-15b = 42 + -12

Combine like terms: 42 + -12 = 30
-15b = 30

Divide each side by '-15'.
b = -2

Simplifying
b = -2