Question

M(8, 4) is the midpoint of RS. If R(-1, 9), what are the coordinates of S?

Answer 1

S is (17,-1)

Since M is the midpoint of RS, you can duplicate the distance from R to M on the other side of M to get S.

From R to M, its 5 points down and 9 points to the right.

Now, starting at point M, move 5 points down and 9 points to the right and you'll get (17,-1).

See visual in photo below.

Hope this helps!

Let me know if you need anything else :)