SOLUTION: Susan is driving on the highway. She begins the trip with 18 gallons of gas in her car. The car uses up one gallon of gas every 25 miles. Let G represent the number of

Algebra ->  Linear-equations -> SOLUTION: Susan is driving on the highway. She begins the trip with 18 gallons of gas in her car. The car uses up one gallon of gas every 25 miles. Let G represent the number of      Log On


   

Question 1047415: Susan is driving on the highway. She begins the trip with
18
gallons of gas in her car. The car uses up one gallon of gas every
25
miles.
Let
G
represent the number of gallons of gas she has left in her tank, and let
D
represent the total distance (in miles) she has traveled. Write an equation relating
G
to
D
, and then graph your equation using the axes below
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
Rate is %2825%2F1%29%28miles%2Fgallon%29 or %281%2F25%29%28gallons%2Fmiles%29.

G, amount of fuel in gallons, in the tank.
Initial data point, ordered pair as (D,G), would be (0,18).
You want an expression to calculate G gallons of gasoline (or fuel), so pick the slope %281%2F25%29%28gallons%2Fmiles%29. The data point identified is an axis intercept, on the vertical axis (meaning on the G axis).

highlight%28G=-%281%2F25%29D%2B18%29
The slope is really negative because the car is consuming amount of fuel, not gaining amount of fuel.