(21b-1)-5(4b+1)=-5

Solution for (21b-1)-5(4b+1)=-5 equation:

Simplifying
(21b + -1) + -5(4b + 1) = -5

Reorder the terms:
(-1 + 21b) + -5(4b + 1) = -5

Remove parenthesis around (-1 + 21b)
-1 + 21b + -5(4b + 1) = -5

Reorder the terms:
-1 + 21b + -5(1 + 4b) = -5
-1 + 21b + (1 * -5 + 4b * -5) = -5
-1 + 21b + (-5 + -20b) = -5

Reorder the terms:
-1 + -5 + 21b + -20b = -5

Combine like terms: -1 + -5 = -6
-6 + 21b + -20b = -5

Combine like terms: 21b + -20b = 1b
-6 + 1b = -5

Solving
-6 + 1b = -5

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 + 1b = -5 + 6

Combine like terms: -6 + 6 = 0
0 + 1b = -5 + 6
1b = -5 + 6

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

Divide each side by '1'.
b = 1

Simplifying
b = 1