SOLUTION: At a restaurant one family ordered 6 burgers and 5 fries, paying $68. Another family ordered 4 burgers and 7 fries, paying $75. Find the cost of 1 burger, and find the cost of 1 o

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: At a restaurant one family ordered 6 burgers and 5 fries, paying $68. Another family ordered 4 burgers and 7 fries, paying $75. Find the cost of 1 burger, and find the cost of 1 o      Log On


   

Question 1073390: At a restaurant one family ordered 6 burgers and 5 fries, paying $68. Another family ordered
4 burgers and 7 fries, paying $75. Find the cost of 1 burger, and find the cost of 1 order of fries.
Found 2 solutions by jorel1380, josgarithmetic:
Answer by jorel1380(3719) About Me  (Show Source):
You can put this solution on YOUR website!
Let b be burgers and f be fries. Then:
6b+5f=68
4b+7f=75
So:
42b+35f=476
20b+35f=375
22b=476-375=101
b=$4.59
f=$8.09
Burgers are $4.59 each; and fries are $8.09 each. ☺☺☺☺

Answer by josgarithmetic(39620) About Me  (Show Source):
You can put this solution on YOUR website!
x burgers
y fries
system%286x%2B5y=68%2C4x%2B7y=75%29


Multiply first equation by 2 and second equation by 3.
12x%2B10y=136%2C12x%2B21y=225

11y=89
y=89%2F11----------One order of fries, $8.09.



6x=68-5y
x=%2868-5y%29%2F6
x=%2868-5%2A8.09%29%2F6
x=4.59-------------One burger, $4.59.