105=8x+13x

Solution for 105=8x+13x equation:

Simplifying
105 = 8x + 13x

Combine like terms: 8x + 13x = 21x
105 = 21x

Solving
105 = 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.
105 + -21x = 21x + -21x

Combine like terms: 21x + -21x = 0
105 + -21x = 0

Add '-105' to each side of the equation.
105 + -105 + -21x = 0 + -105

Combine like terms: 105 + -105 = 0
0 + -21x = 0 + -105
-21x = 0 + -105

Combine like terms: 0 + -105 = -105
-21x = -105

Divide each side by '-21'.
x = 5

Simplifying
x = 5