1) you can actually answer this one without a graph. Just plug in each coordinate until you find one that doesn't work. In this case, the point (-1,2) doesn't work, so your answer is A.
2) In order for a relation to be a function, each x value must only have one y value. Both (2,2) and (2,3) have the same x value but different y values. Removing one of these two would make it a function. C.
3) If you solve the equation for y, you would get y = -1/2x - 3/4, so the slope is -1/2. D.
4) this one is similar to #1 except you are looking for a point that does work. When you plug in the points, you find that D (1,0) is the only point that works.