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In trapezoid $abcd$, the parallel sides $ab$ and $cd$ have lengths of 8 and 20 units, respectively, and the altitude is 12 units. points $e$ and $f$ are the midpoints of sides $ad$ and $bc$, respectively. what is the area of quadrilateral $efcd$ in square units?

2 Answers

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Answer:

C-75 Third Option

Explanation:

In trapezoid $abcd$, the parallel sides $ab$ and $cd$ have lengths of 8 and 20 units-example-1
User Shady Smaoui
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7.3k points
3 votes
1.

EF is the median of the trapezoid ABCD, thus


|EF|= (|AB|+|DC|)/(2)= (20+8)/(2)=14 units.

2.

The median EF bisects the altitude into 2 segments of equal length 6 units.

Thus the height of trapezoid EFCD is 6, and its 2 bases have length 14 and 8 units.

3.

From the area of the trapezoid formula:


A_E_F_C_D=Height* (Base_1+Base_2)/(2)=6* (14+8)/(2)=6* (22)/(2)=66 (square units)


Answer: 66 square units
In trapezoid $abcd$, the parallel sides $ab$ and $cd$ have lengths of 8 and 20 units-example-1
User Jakea
by
6.8k points