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Question

One endpoint of a line segment is (4,3) and its midpoint is (2,9). What is the sum of the coordinates of the other endpoint?

Accepted Answer

Let the other endpoint be (x, y). We know that 4 + x2 + 3 + y2 = 2 + 9 = 11. Thus, 7 + x + y = 22, and x + y = 15.