Question

what is the area? 3 km 5 km 7 km square kilometers

Explanation:

Step1: Recall trapezoid area formula

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

Step2: Identify values of $a$, $b$ and $h$

Here, $a = 3$ km, $b = 7$ km, and $h = 5$ km.

Step3: Substitute values into formula

$A=\frac{(3 + 7)\times5}{2}=\frac{10\times5}{2}$.

Step4: Calculate the result

$\frac{10\times5}{2}=\frac{50}{2}=25$ square kilometers.

Answer:

25