Find the coordinates of the missing endpoint if m is the midpoint of xy
20) x(-11,-6) m(15,4)
21) m(-4,8) y(19,0)

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.