Answer:
4x-4y=20 divide by 4 to get
x-y=5, now substitute -5 for y
x-(-5) = 5
x+5 = 5
x = 0
or you could immediately notice that by letting y=-5
that
4x +20 = 20 and
4x = 0
x = 0
x-y=5 is the same as
y= x-5 which graphically has slope = 1 with y intercept y=-5
x-intercept is x=5. Plot those two intercepts or points (0,-5) and (5,0) connect them with a straight line. It has slope = 1 or a 45 degree angle with the horizontal.
Step-by-step explanation: