Without a second independent equation, it's not a 'system' yet.
Any pair of numbers where the 'y' is 5 more than the 'x'. There are an infinite number of suitable pairs. 2y-2x=10 2y-2x+2x=10+2x 2y=2x+10 divide both side by 2. y=x+5
The two equations are linear.
It doesn't look like you have anything that can be determined. The most confusing part of this is the -2x 2y = -4
-2x=2y+5 +2x -2y -2y=2x+5 /-2 y=-1/1+2.5
The solution is:- x = 0 and y = 5
The slope of the line of 2x plus 2y equals 7 is (7/2x - 1).
x = 3 and y = 2
x = 0 & y = -3
get it to y= -2y = 1 - 2x y = x - 0.5
x+2y-2x-y=x y-x=x y=2x