Function

Module 2 Functions

Answer the following questions and if required to do calculations please show your work:

1. Evaluate the function f(x) = 9x - 6 for x=0 and x=5.

Answers: f (0) = 9(0) - 6=-6 f (5) = 9 (5)-6=39

2. Bob owns a watch repair shop. He has found that the cost of operating his shop is given by C(x) = 4x2-296x+85 , where c is cost and x is the number of watches repaired. How many watches must he repair to have the lowest cost?

Answer: C(x) = 4x2-296x+85

C(x) =4(x^2-74x+37^2) +85-4(37^2)

C(x) =4(x-37) ^2+85-5476

C(x) =4(x-37) ^2-5391

(37, -5391) Bob must sell 37 watches to have lowest operating cost.

3. Find the slope of the line through the points ( 5, -5) and ( 6, -1)

4. Kafka Inc. imports hard drives and sells them on the internet. The profit is given by the equation P = 140n - 8500, where n is the number of hard drives sold. Graph P = 140n - 8500 for n < 1000. Estimate the profit, to the nearest ten dollars, corresponding to the sale of 875 hard drives.

Graph:

p=140n-8550 profit p=140x875 - 8550 = $113,950 estimated cost of sale.

5. When $ 8600 is invested in a savings account paying simple interest for the year, the interest, i in dollars, can be obtained from the equation i = 8600r , where r is the rate of interest in decimal form. Graph i = 8600r, for r up to and including a rate of 15%. If the rate is 12%, how much interest is earned?

Y= 8600* .12*x

Y=$1032.00

*** Bold marks are answers provided*****