Math
posted by Andrea .
According to a rating agency, a car's MPG (miles per gallon) ratings are: 25 MPG for city and 30 MPG for highway driving. A driver spent $20.00 (the gasoline costs $1.25/gallon) on a combined city and highway trip of 450 miles. How many miles "C" in city and "H" on highway was the car driven ?
I need to get two equations out of this and use the substitution or elimination method to solve this problem.

Let C = 450  H
$1.25 (30H + 25C) = $20
Substitute the value of C in the first equation into the second. Solve for H. Put value of H into the first equation to solve for C. Check by putting both values into the second equation.
I'll let you do the calculations. I hope this helps. Thanks for asking.