Systems of Linear Equations?

Question

Can somebody help me with this homework problem, I'm very stumped as to how I should approach this:
Harry wants to know how many miles his car gets in city driving and how many it gets in highway driving. Harry kept track of his car's mileage and found that on 9 gallons of gasoline he was able to drive a combination of 96 miles in the city and 160 miles on the highway. On 11 gallons of gas, he was able to drive a combination of 144 miles in the city and 160 miles on the highway. Using this info find how many miles per gallon his car gets in city driving and how many it gets in highway driving.

Answer 1

k
c = city mpg
h = highway mpg

96/c +160/h=9
144/c + 160/h=11

subtract the first from the second
48/c=2
c=24mpg
plug into the first
96/24 +160/h = 9
9-4=160/h
h=160/5
h=32 mpg

check
144/24 +160/32 = 11
6+5=11 it checks

j

Answer 2

from that an extra 2 gallons gets him 144-96 =48miles in the city

so it will take 2 gallons to drive 48miles in the city
equals to 1 gallons to drive 24miles in the city

96miles in the city will take 4 gallons
therefore 160miles in the highway will take 5 gallons
equals 1 gallon will take you 32miles

therefore 1 gallon will give you 24miles in the city
and 32 miles in the highway