Question

200 3. A technician charges $25 per hour plus $50 for a house call to repair home computers. Make a table and a graph to show the cost for 1,2,3, and 4 hours of home computer repair service. Is there a direct variation? Exempe 31 150 ($) 1809 100 50 Time (h) Charge (9) 0 1 2 3 4 5 6 Time (h) Your answer

Answer 1

Recall that for a home visit, the technician charges $50 regardless on the time spent in the repair.

So, to find out the rate, we should calculate the part that depends on the spent time, and the add 50. So for example, we know that the technician spents 1 hour. So, we multiply 1 times 25 and then add 50. So, 25*1 + 50 = 75, which is the rate for a 1-hour repair.

So, in general, if we know that the number of hours is x, we multiply x times 25 and then add 50. Then a table would like this:

x 25*x 25*x +50

1 25 75

2 50 100

3 75 125

4 100 150

Note that as the time increases by one hour, the fare increases by 25. This is an example of a direct variation, since as the independent variable increases (t