Point are set up (x,y) you sub the number for x into the equation and see if you get the number for y. y=4x+3 y=4 (5)+3 y=20+3 y=23 so A isn't the answer
y=4 (17)+3 y=68+3 y=71 B isn't the answer
y=4 (4)+3 y=16+3 y=19 and because 4 is the x value for c and d and there can only be 1 y value for each x you're answer is C because when x=4 y =19 or (4,19)