What is the formula of base 1 in trapezoid?

Sagot :

b1=((2A)/h)-b2 is the formula,just rearrange
The original formula of the trapezoid is
A=1/2(b1+b2)(h)
Multiply both sides by 2
2A=(b1+b2)(h)
Divide both sides by h
2A/h=b1+b2
Subtract b2 from both sides
2A/h -b2=b1 
or simply
(2A-b2h)/h=b1

Hope this helps =)