Which correctly shows the area formula for a trapezoid, A=1/2h(b1+b2) , rearranged for the quantity of interest h?

Question

h=12A(b1+b2) h equals Start Fraction 1 over 2 End Fraction upper A left parenthesis b subscript 1 baseline plus b subscript 2 baseline right parenthesis b1=2Ah−b2 b subscript 1 baseline dequals Start Fraction 2 upper A over h End Fraction minus b subscript 2 baseline h=b1+b22A h equals Start Fraction b subscript 1 baseline plus b subscript 2 baseline over 2 upper A End Fraction h=2Ab1+b2 h equals Start Fraction 2 upper A over b subscript 1 baseline plus b subscript 2 baseline End Fraction

Answer 1

h = 2A / (b1 + b2)