The answer is D because to find the slope of a line that is perpendicular to another, you have to find the opposite reciprocal. so here the slope would be -1/4. now, take that slope and put it into an equation. like the following:
now to find b you must insert the points into the equation (plug in 4 for x, and 15 for y).
b then equals 16. so, the answer is D.
now to find b you must insert the points into the equation (plug in 4 for x, and 15 for y).
b then equals 16. so, the answer is D.