Answer:
The length of WX is 31 units.(third option)
Explanation:
Given that In trapezoid WXYZ, WX║ZY and S and T are the mid points of the sides WZ and XY. We have to find the length of WX.
By trapezoid mid-segment Property,
A mid-segment of a trapezoid join the midpoints of the two non-parallel sides of trapezoid. The length of the mid-segment is the average of the lengths of the two bases and is parallel to the bases of the trapezoid.
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The length of WX is 31 units.(third option)