SOLUTION: Roger bought five bags of pretzels and three calculators for $31. Stephen bought twenty bags of pretzels and a calculator for $47. Emily bought two bags of pretzels and five calcul
Question 378654: Roger bought five bags of pretzels and three calculators for $31. Stephen bought twenty bags of pretzels and a calculator for $47. Emily bought two bags of pretzels and five calculators. How much did she pay? Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website! Roger bought five bags of pretzels and three calculators for $31. Stephen bought twenty bags of pretzels and a calculator for $47. Emily bought two bags of pretzels and five calculators. How much did she pay?
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let pretzels cost $x each
calculators cost $y each
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ROGER
5x+3y=31............................1
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Stephen
20x+y=47............................2
multiply (10 by -4
-20x-12y=-124
add it to(2)
20x-20x+y-12y=-124+47
-11y=-77
/-11
-11y/-11= -77/-11
y=$ 7 cost of calculator
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Plug the value of y in (2)
20x+y =47
20x+7=47
-7
20x+7-7=47-7
20x=40
/20
20x/20=40/20
x= $ 2 the price of pretzels
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Plug value of x&y to find how much emily paid
m.ananth@hotmail.ca
