Could some help me on this.(algebra 1)

Rose bought a new hat when she was on vacation. the following formula describes the percent sales tax rose paid b=t-c/c

If on=8x-8,lm=7x+4,nm=x-5,and ol=3y-6

Afamily has two cars. the first car has a fuel efficiency of 25 miles per gallon of gas and the second has a fuel efficiency of 15 miles per gallon of gas. during one particular week, the two cars went a combined total of 1025 miles, for a total gas consumption of 55 gallons. how many gallons were consumed by each of the two cars that week?