Answer is (4,3)
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Add up the x coordinates to get 9+(-1) = 8. Divide this over two and we end up with 8/2 = 4
Repeat for the y coordinates: 9+(-3) = 6, which cuts in half to get 6/2 = 3
The midpoint is at (4,3)
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The midpoint formula is
[tex]\left(\frac{x_1+x_2}{2},\frac{y_1+y_2}{2}\right)[/tex] where (x1,y1) and (x2,y2) are the endpoints.
