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Find the Intersection Using the Midpoint

The applet below contains a parallelogram graphed in the coordinate plane. Notice how 3 of its vertices have variable coordinates. Note that one vertex is fixed at (0,0). You can move the BIG POINTS anywhere you'd like.

Given that 0 has coordinates (0,0), move the points N to (6,0), M to (7,4), and L to (1,4) in the graph above.Move the line segments above the parallelogram using their points to draw and . (Remember they were called the "diagonals" of a parallelogram.) Move point P to their intersection. What do you get as its coordinates? Write the coordinate values in a pair (e.g., "(2,3).")

Recall the theorem we've proven:
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Back to our diagram: How will you use the Parallelogram Diagonals Theorem to find the coordinates of the intersection? By the Parallelogram Diagonals Theorem, the diagonals of a parallelogram bisect each other. So, the coordinates of the intersection are the (fill-in-the-blank) of diagonals and .

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In the applet above, recall the values of the coordinates of the points O and M. Designate them as (x1,y1) and (x2,y2). I already did it for O: O = (x1,y1) = (0,0) M = (x2,y2) = (fill-in-the-blank)

Finally, using the Midpoint Formula, find the midpoint of O and M.

Does the midpoint you found in Step 4 match where you placed the point P in the applet above? Why or why not?