Answer:
- cheeseburger: 470 calories
- fries: 380 calories
Explanation:
The given relations let you formulate two equations in the two unknown values. These can be solved by any of the usual methods.
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setup
Let x represent the caloric content of a cheeseburger, and y the caloric content of a small order of fries. The problem statement tells us ...
2x +y = 1320
3x +2y = 2170
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solution
Subtracting the second equation from twice the first gives ...
2(2x +y) -(3x +2y) = 2(1320) -(2170)
x = 470
Using the first equation, we can find y:
y = 1320 -2x = 1320 -2(470) = 380
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A cheeseburger has 470 calories; a small order of fries, 380 calories.
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Attached is a graphing calculator solution.