Question

Question #d575c

Answer 1

The formula for a rectangle is A=bh. A trapezoid has a different top and bottom, but a constant height. If you average the top and bottom lengths `((b1 + b2)) / 2`, you can use this as the base and find the area of the trapezoid.

Explanation:

The official formula is `A = ½ h (b1+b2).` This is the same thing, but rearranged. It is easier than it looks.

Answer 2

`color(blue)(h) = (2A)/((b_1+b_2))`

Explanation:

To change the formula around, I like to have the 'subject' on the left side first and then keep it there, getting rid of all the other variables and numbers bit by bit.

`1/2color(blue)(h)(b_1+b_2) = A`

To get rid of `1/2`, multiply both sides by `2` and cancel.

`cancel2xx 1/cancel2color(blue)(h)(b_1+b_2) = 2xxA" "` this leaves:

`color(blue)(h)(b_1 +b_2) = 2A`

Now, to get the `color(blue)(h)` on its own, divide by the whole bracket.

`color(blue)(h) = (2A)/((b_1+b_2))`