The area of the trapezoid below is 72 square inches. What is the length of the altitude DE?

Question

campbell_st · Answer

do you know the lengths of the parallel sides...?

acxbox22 · Answer

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acxbox22 · Answer

where is the trapezoid below?

campbell_st · Answer

so using the formula 

$$72 = \frac{h}{2}\times (a + b)$$

h = height  and a and b are the lengths of the parallel sides

which can be written as 

$$144 = h \times (a + b)$$

then 

$$\frac{144}{(a + b)} = h$$

anonymous · Answer

The top of it is 14 and the bottom of it is 22.

acxbox22 · Answer

A=(b1+b2)h/2
A=(22+14)h/2
72=36h/2

144=36h
---------
      36
height/altitude=4 units

campbell_st · Answer

so substitute the values for a and b into the modified form of the area fromula to find the height