Question

Jabari is power washing houses for a summer job. For every job, he charges an initial fee plus $30 for each hour of work. His total fee for a 4-hour job, for instance, is

$170.

Answer 1

so what is the question here? if he is paid $30 an hour for 4 hours that is $120 if the total fee is $170 then the initial fee for the job is $50.

Answer 2

The initial fee is $50.

Explanation:

We will write an equation in slope-intercept form to solve this.

We know the slope, or rate of change, is $30. This gives us

y = 30x + b

We do not know the y-intercept, which is the initial fee.

We know that for a 4 hour job, he charges $170. We can substitute the total cost in for y and the number of hours in for x:

170 = 30(4) +b

170 = 120 + b

Subtract 120 from each side:

170-120 = 120+b-120

50 = b

The initial fee is $50.