Question

area of a trapezoid

1. a = ______

Explanation:

Step1: Identify trapezoid - area formula

The formula for the area of a trapezoid is $A=\frac{(b_1 + b_2)h}{2}$, where $b_1$ and $b_2$ are the lengths of the parallel - sides and $h$ is the height.

Step2: Identify values of $b_1$, $b_2$ and $h$

From the figure, $b_1 = 8$ ft, $b_2=10$ ft and $h = 11$ ft.

Step3: Substitute values into formula

$A=\frac{(8 + 10)\times11}{2}$.
First, calculate the sum of the parallel sides: $8+10 = 18$ ft.
Then, multiply by the height: $18\times11=198$ square - feet.
Finally, divide by 2: $A=\frac{198}{2}=99$ square - feet.

Answer:

$99$ square feet