Question

in trapezoid abcd, ab||cd and ab⊥bc. what is the area of this trapezoid? 630 cm² 450 cm² 360 cm² 315 cm²

Explanation:

Step1: Identify trapezoid formula

The area formula for 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. Here, the parallel sides are $AB = 12$ cm and $CD=30$ cm, and the height $BC = 15$ cm.

Step2: Substitute values into formula

$A=\frac{(12 + 30)\times15}{2}$. First, calculate the sum of the parallel sides: $12+30 = 42$ cm. Then, multiply by the height: $42\times15=630$ $cm^{2}$. Finally, divide by 2: $\frac{630}{2}=315$ $cm^{2}$.

Answer:

$315$ $cm^{2}$