7x - 3y = 24
7x - 24 = 3y
(7x - 24) : 3 = y
Because they find it to look stylish.
Let t be the number of tolls they crossed.
Amount they spent at each toll = $1.75.
Amount they spent at gas station = $28.
Let C be the total amount they spent on gas and tolls.
If they crossed 1 toll, then
C = 28 + 1.75(1).
If they crossed 3 tolls, then,
C = 28 + 1.75(3)
If they crossed t tolls, then,
C = 28 + 1.75t
Here, the terms are 28 and 1.75t and the factors are 1.75 and t.
The answer is 17! Hope it helps :)