112k views
13 votes
Solve the system by substitution
2y-2x=8;x+y=14

2 Answers

4 votes

Solve for the first variable in one of the equations, then subsitute the result into the other equation.

Point Form: (5, 9)

Equation Form: x = 5, y = 9

User SaltyNuts
by
5.0k points
9 votes
Answer:

Simplifying
2y + -2x = 8

Reorder the terms:
-2x + 2y = 8

Solving
-2x + 2y = 8

Solving for variable 'x'.

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

Add '-2y' to each side of the equation.
-2x + 2y + -2y = 8 + -2y

Combine like terms: 2y + -2y = 0
-2x + 0 = 8 + -2y
-2x = 8 + -2y

Divide each side by '-2'.
x = -4 + y

Simplifying
x = -4 + y
___________________________________

Simplifying
x + y = 14

Solving
x + y = 14

Solving for variable 'x'.

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

Add '-1y' to each side of the equation.
x + y + -1y = 14 + -1y

Combine like terms: y + -1y = 0
x + 0 = 14 + -1y
x = 14 + -1y

Simplifying
x = 14 + -1y

Hope that helps you :)
User Kacey
by
4.3k points