3(x-1)-(x-9)=20

Solution for 3(x-1)-(x-9)=20 equation:

Simplifying
3(x + -1) + -1(x + -9) = 20

Reorder the terms:
3(-1 + x) + -1(x + -9) = 20
(-1 * 3 + x * 3) + -1(x + -9) = 20
(-3 + 3x) + -1(x + -9) = 20

Reorder the terms:
-3 + 3x + -1(-9 + x) = 20
-3 + 3x + (-9 * -1 + x * -1) = 20
-3 + 3x + (9 + -1x) = 20

Reorder the terms:
-3 + 9 + 3x + -1x = 20

Combine like terms: -3 + 9 = 6
6 + 3x + -1x = 20

Combine like terms: 3x + -1x = 2x
6 + 2x = 20

Solving
6 + 2x = 20

Solving for variable 'x'.

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

Add '-6' to each side of the equation.
6 + -6 + 2x = 20 + -6

Combine like terms: 6 + -6 = 0
0 + 2x = 20 + -6
2x = 20 + -6

Combine like terms: 20 + -6 = 14
2x = 14

Divide each side by '2'.
x = 7

Simplifying
x = 7