SOLUTION: Suppose you bought supplies for a party. Three rolls of streamers and 15 party hats cost $30. Later, you bought 2 rolls of streamers and 4 party hats for $11. How much did each rol

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: Suppose you bought supplies for a party. Three rolls of streamers and 15 party hats cost $30. Later, you bought 2 rolls of streamers and 4 party hats for $11. How much did each rol      Log On


   

Question 104831This question is from textbook Pretice hall mathematics. Algebra 1
: Suppose you bought supplies for a party. Three rolls of streamers and 15 party hats cost $30. Later, you bought 2 rolls of streamers and 4 party hats for $11. How much did each roll of streamers cost? How much did each party hat cost?
K you have to write a linear equation and then solve it. Please help. This question is from textbook Pretice hall mathematics. Algebra 1

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
let s=streamers, p=hats

Three rolls of streamers and 15 party hats cost $30 ... 3s+15p=30 ... s+5p=10 ... s=10-5p

you bought 2 rolls of streamers and 4 party hats for $11 ... 2s+4p=11

substituting from first equation to second ... 2(10-5p)+4p=11 ... 20-10p+4p=11 ... -6p=-9

solve for p and substitute back to find s