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An equation where variables are used to represent known values—function notation true or false

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.

Sioux co. replaced the roof on its existing building, therefore increasing the building's life by 10 years. the cost of the roof is considered a(n):