Find the other endpoint

Question

Find the coordinates of the other endpoint of the​ segment, given its midpoint and one endpoint.​ (Hint: Let​ (x,y) be the unknown endpoint. Apply the midpoint​ formula, and solve the two equations for x and​ y.)

midpoint ​(10​,3​), endpoint (5​,−3​)

Answer 1

(15,9) so that midpoint is average of end points = ((15+5)/2, (9-3)/2) = (10,3)