A=1/2h(B=b) (for b)area of a trapezoid

1 answer

The correct formula is
A=(1/2)h(B+b)
B and b are the lengths of the two parallel sides and h is the distance beween them

Now... what exactly is your question?

If you want to solve for b, that can be done as follows:
B+b = (2A/h)
b = (2A/h) -B