Question 1012206: theorem 6. the median of a trapezoid to each base and its lenght is one half the sum of the lenghts of the bases
to prove the theorem . Found 2 solutions by ikleyn, solver91311:Answer by ikleyn(53862) (Show Source):
You can put this solution on YOUR website! .
the median of a trapezoid to each base and its lenght is one half the sum of the lenghts of the bases
to prove the theorem
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Since the shape and size of a plane figure is invariate under coordinate translations and rotations, a general trapezoid can be placed with one vertex at the origin and one base coincident with the -axis without loss of generality. See figure 1:
Figure 1
Using the Midpoint formulae, the coordinates of the endpoints of the median are established as shown in figure 2:
Figure 2:
Since the line segments forming the bases and the median are horizontal lines, the measures can be determined by simple differences of the -coordinates.
The measure of the lower base is simply , the measure of the upper base is . Half of the sum of the bases is then . Compare with the measure of the median: Q.E.D.
John
My calculator said it, I believe it, that settles it