I’m pretty sure I know the answer but I just wanna check myself, thanks :)

Which expression can be used to determine the slope of the line that passes through the points -6, three and one, -9

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 . jabari's total fee,f, for a single job is a function of the number,t, of hours it takes him to complete the job. write the function's formula.

Which equation represents the function on the graph?