The formula for the area of a trapezoid is a = 1/2 (b+b) h. explain why the bases of a trapezoid need to be added in the formula

Step-by-step explanation:

Look at the picture.

We connect two congruent trapezoids as in the picture.

We created a parallelogram with a base length of b₁ + b₂ and a height h equal to the height of the trapezoid.

The formula of an area of a parallelogram:

The area of the trapezoid is half of the parallelogram area.

Therefore we have the formula of an area of trapezoid:

Therefore we need to be added the bases of a trapezoid.

E and F but read below.

Step-by-step explanation:

I'm reading the legs as 6 and 6 so the triangle is at least isosceles.

The question is, is it also a right angle? If it is, then the Hypotenuse is incorrectly rounded. When you calculate the hypotenuse, it comes to 8.485 which should be rounded to 8.5

Regardless of that, I think the answer is intended to by a right triangle, but don't be surprised if your marker does not agree.