Explain why the bases of a trapezoid need to be added in the formula.

PL HELP

Step-by-step explanation:

Because if you put together two trapezoids, one in a reversed position, you get a paralelogram. There the side of the parallelogram is the sum of the trapezoid bases, as in the picture.

The are of paralelogram is: A=(b+B)×h

For trapezoid, half of parallelogram:

A1=A/2=(b+B)×h/2

it’s the first one your welcome