Answer:
D
Step-by-step explanation:
a is false since x could be 0.
b is easy to check, just plug numbers in, and we can see that it's false(you would get 0+0=1 and -0-0=-1 once plugged in)
c is also easy to check, just plot the line or simplify the first equation. since (2x+2y)/2=4/2 is also x+y=2, the second equation is also x+y=2, so it must have infinitely many solutions.
d must be true due to process of elimination but let's check to make sure.
7y=14x, divide both sides by 7 to get y=2x and since they're the same equation it must mean that they have infinitly many solutions and we can see that it is correct
