Question 1110510
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<pre>
1.  The length of the middle segment of the trapezoid is {{{(1/2)*(11+13)}}} = 12 cm.


2.  The area of the trapezoid is the product of the middle segment length by the altitude:


        Area = 12*h = 84,


    which implies  h = {{{84/12}}} = 7 cm  for the altitude.
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Solved.