Question

what is the area of the trapezoid? 5 km 4 km 3 km 9 km square kilometers

Explanation:

Step1: Recall trapezoid area formula

The area of a trapezoid is given by $\frac{1}{2} \times (a + b) \times h$, where $a$ and $b$ are the lengths of the two parallel sides, and $h$ is the height between them.

Step2: Identify given values

Here, $a = 5\ \text{km}$, $b = 9\ \text{km}$, $h = 3\ \text{km}$.

Step3: Substitute values into formula

$\frac{1}{2} \times (5 + 9) \times 3$

Step4: Calculate step-by-step

First compute the sum inside the parentheses: $5 + 9 = 14$.
Then multiply by the height: $14 \times 3 = 42$.
Finally multiply by $\frac{1}{2}$: $\frac{1}{2} \times 42 = 21$.

Answer:

21 square kilometers