Answer:
d. x +y = 0
Step-by-step explanation:
You want to know the equation that (b, -b) is the solution to.
We can see that the ordered pair (x, y) has x=b and y=-b. These are not equal, so this is not the solution to y=x. (These considerations eliminate answer choices A, B, C.)
The equation of choice D can be rearranged to ...
x +y = 0
y = -x
Then if x=b, we have ...
y = -x = -b
The solution to the equation x + y = 0 is (b, -b), choice D.
