SOLUTION: Joe PAYS 372 for 24 gallons of paint. If the indoor paint costs $12 per gallon, and the outdoor paint costs $18per gallon, how many gallons of each did he buy?

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Joe PAYS 372 for 24 gallons of paint. If the indoor paint costs $12 per gallon, and the outdoor paint costs $18per gallon, how many gallons of each did he buy?      Log On


   

Question 796147: Joe PAYS 372 for 24 gallons of paint. If the indoor paint costs $12 per gallon, and the outdoor paint costs $18per gallon, how many gallons of each did he buy?
Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
x for gallons of indoor paint
y for gallons of outdoor paint

Account for cost: 12%2Ax%2B18%2Ay=372

Account for gallons of paint: x%2By=24

Simplify the cost equation.
2x%2B3y=62

Most comfortable is maybe use elimination. Multiply the gallons equation by 2 and subtract from the simplified cost equation.
%282x%2B3y%29-%282x%2B2y%29=62-%282%2A24%29
.
y=62-48
highlight%28y=14%29.

NOW can you find the value for x on your own?-----(BIG Hint is use the original gallons account equation)