(x+2x)+(y+y-6)=78

Solution for (x+2x)+(y+y-6)=78 equation:

Simplifying
(x + 2x) + (y + y + -6) = 78

Combine like terms: x + 2x = 3x
(3x) + (y + y + -6) = 78
(3x) + (y + y + -6) = 78

Reorder the terms:
(3x) + (-6 + y + y) = 78

Combine like terms: y + y = 2y
(3x) + (-6 + 2y) = 78

Remove parenthesis around (-6 + 2y)
(3x) + -6 + 2y = 78

Reorder the terms:
-6 + (3x) + 2y = 78

Solving
-6 + (3x) + 2y = 78

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 + (3x) + 6 + 2y = 78 + 6

Reorder the terms:
-6 + 6 + (3x) + 2y = 78 + 6

Combine like terms: -6 + 6 = 0
0 + (3x) + 2y = 78 + 6
(3x) + 2y = 78 + 6

Combine like terms: 78 + 6 = 84
(3x) + 2y = 84

Add '-2y' to each side of the equation.
(3x) + 2y + -2y = 84 + -2y

Combine like terms: 2y + -2y = 0
(3x) + 0 = 84 + -2y
(3x) = 84 + -2y

Divide each side by '3'.
x = 28 + -0.6666666667y

Simplifying
x = 28 + -0.6666666667y