(2x-10)+(x-20)=90

Solution for (2x-10)+(x-20)=90 equation:

Simplifying
(2x + -10) + (x + -20) = 90

Reorder the terms:
(-10 + 2x) + (x + -20) = 90

Remove parenthesis around (-10 + 2x)
-10 + 2x + (x + -20) = 90

Reorder the terms:
-10 + 2x + (-20 + x) = 90

Remove parenthesis around (-20 + x)
-10 + 2x + -20 + x = 90

Reorder the terms:
-10 + -20 + 2x + x = 90

Combine like terms: -10 + -20 = -30
-30 + 2x + x = 90

Combine like terms: 2x + x = 3x
-30 + 3x = 90

Solving
-30 + 3x = 90

Solving for variable 'x'.

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

Add '30' to each side of the equation.
-30 + 30 + 3x = 90 + 30

Combine like terms: -30 + 30 = 0
0 + 3x = 90 + 30
3x = 90 + 30

Combine like terms: 90 + 30 = 120
3x = 120

Divide each side by '3'.
x = 40

Simplifying
x = 40