Step 1) Solve the first equation for x:
x - y = 3
x - y + color(red)(y) = 3 + color(red)(y)
x - 0 = 3 + y
x = 3 + y
Step 2) Substitute 3 + y for x in the second equation and solve for y:
2x + 2y = 2 becomes:
2(3 + y) + 2y = 2
(2 * 3) + (2 * y) + 2y = 2
6 + 2y + 2y = 2
6 + (2 + 2)y = 2
6 + 4y = 2
-color(red)(6) + 6 + 4y = -color(red)(6) + 2
0 + 4y = -4
4y = -4
(4y)/color(red)(4) = -4/color(red)(4)
(color(red)(cancel(color(black)(4)))y)/cancel(color(red)(4)) = -1
y = -1
Step 3) Substitute -1 for y in the solution to the first equation at the end of Step 1 and calculate x:
x = 3 + y becomes:
x = 3 + (-1)
x = 3 - 1
x = 2
The solution is: x = 2 and y = -1 or (2, -1)
