Question

The area of a trapezoid is found using the formula 2003-01-03-00-00_files/i0080000.jpg, where 2003-01-03-00-00_files/i0080001.jpg and 2003-01-03-00-00_files/i0080002.jpg are the parallel sides of the trapezoid and h is the height of the trapezoid. What is the area, in square kilometers, of a trapezoid with bases 5 km and 7 km and height 3 km?
A.
14.5
B.
18
C.
36
D.
52.5

Answer 1

A quadrilateral's area is equal to the average of the base lengths times the height.
\[trapezoid=\frac{ h(b1+b2) }{ 2 } \]
so it would look like this
\[trapezoid=\frac{ 3(5+7) }{ 2 }=\frac{ 3(12) }{ 2 }=\frac{ 36 }{ 2 }=18km ^{2}\]