42=8x+13x

Solution for 42=8x+13x equation:

Simplifying
42 = 8x + 13x

Combine like terms: 8x + 13x = 21x
42 = 21x

Solving
42 = 21x

Solving for variable 'x'.

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

Add '-21x' to each side of the equation.
42 + -21x = 21x + -21x

Combine like terms: 21x + -21x = 0
42 + -21x = 0

Add '-42' to each side of the equation.
42 + -42 + -21x = 0 + -42

Combine like terms: 42 + -42 = 0
0 + -21x = 0 + -42
-21x = 0 + -42

Combine like terms: 0 + -42 = -42
-21x = -42

Divide each side by '-21'.
x = 2

Simplifying
x = 2