Round each number and then do what the problem asks you to do wether that be subtraction or addition.
Rays CA and CB form the angle ACB
Since we are given no other function, we have to assume that P(x) is the "function from part d".
The average rate of change of P(x) on the interval [60, 80] is given by
rate of change = (P(80) - P(60))/(80 - 60) = (304 -320)/20 = -0.8
The average rate of change of P(x) over [60, 80] is -0.8._____
Units of the rate of change are ($10k)/(1k units) = $10/unit. That is, the profit drops on average $8 per unit on that interval.
Theorems are proven with geometric proof