Question

X is the midpoint of AB. B has coordinates (12,−7), and X has coordinates (3,−1). Identify the coordinates of A.

Answer 1

(-6, 5)

Explanation:

Answer 2

Count the distance in x and y separately from B to X

12 -> 3 = 9 (subtracted) , -7 -> -1 = 6 (added).

X is midpnt, so if we go from B to X, we must go from X to get A.

subtract another 9 from the x value, and add another 6 to the y value of X

That gives us -6, 5, which are the coordinates of A.