The cos of renting a van for one day includes a flat rental fee plus a charge for each mile the van is driven while it is rented. A van that is driven 107 miles costs $97.15. A van that is driven 127 miles costs $106.15. What is the flat rental fee?

(107,97.15), (127,106.15)

slope = (106.15 - 97.15) / (127 - 107) = 9 / 20 = 0.45

y = mx + b

slope (m) = 0.45

(107,97.15) ... x = 107 and y = 97.15

sub into the formula and find b, ur flat rental fee

97.15 = 0.45 (107) + b

97.15 = 48.15 + b

97.15 - 48.15 = b

49 = b < = = ur flat rate fee

so ur equation would be : y = 0.45x + 49 ... this is basically saying that the cost of renting a van will cost u $ 0.45 per mile with the flat rate fee costing u $ 49.

The previous answer seems reasonable, and written out, so I will defer to that.