# The area of a trapezoid is equal to half of the product of the height and sum of the bases. How do you rewrite the expression isolating one of the bases?

Since the area of the trapezium is $A = \left(\frac{1}{2}\right) h \left(a + b\right) = h \frac{a + b}{2}$ where $a$ & $b$ are the two bases.
a + b = 2*(A/h)=> a = 2*(A/h) - b