The area of a trapezoid is given by the formula A=h/2 (a+b) where h is the height of the trapezoid and a and b are the lengths of the two parallel sides. Solve the formula for a.

Suppose that the price p, in dollars, and the number of sales, x, of a certain item follow the equation 4 p plus 4 x plus 2 pxequals56. suppose also that p and x are both functions of time, measured in days. find the rate at which x is changing when xequals2, pequals6, and startfraction dp over dt endfraction equals1.5.