2(3b+21)=13b+7

Solution for 2(3b+21)=13b+7 equation:

Simplifying
2(3b + 21) = 13b + 7

Reorder the terms:
2(21 + 3b) = 13b + 7
(21 * 2 + 3b * 2) = 13b + 7
(42 + 6b) = 13b + 7

Reorder the terms:
42 + 6b = 7 + 13b

Solving
42 + 6b = 7 + 13b

Solving for variable 'b'.

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

Add '-13b' to each side of the equation.
42 + 6b + -13b = 7 + 13b + -13b

Combine like terms: 6b + -13b = -7b
42 + -7b = 7 + 13b + -13b

Combine like terms: 13b + -13b = 0
42 + -7b = 7 + 0
42 + -7b = 7

Add '-42' to each side of the equation.
42 + -42 + -7b = 7 + -42

Combine like terms: 42 + -42 = 0
0 + -7b = 7 + -42
-7b = 7 + -42

Combine like terms: 7 + -42 = -35
-7b = -35

Divide each side by '-7'.
b = 5

Simplifying
b = 5