Question 762281
First car = x
Second car = y
  x +   y = 55.......1
35x + 25y = 1675.....2
Multiply (1) by 25
25x + 25y = 1375...3
35x + 25y = 1675...2
Subtract (3) from (2)
10x      = 300
  x      = 30
Substitute x = 30 into (1)
x + y = 55
30 + y = 55
     y = 55 - 30
     y = 25
First car 30 gallons
Second car 25 gallons