solve for x & y solve y = -x + 7 when y = 2x + 1

Subtract both equations to eliminate y:
y = -x +7
-
y= 2x +1
_______
0= -3x +6
Solve for x:
3x = 6
x= 6/3
x= 2
Replace x on any initial equation and solve for y:
y= -x+7
y= -2+7
y= 5
Solution:
x=2
y=5