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a store is having a sale on chocolate chips and walnuts. for 9 pounds of chocolate chips and 7 pounds of walnuts, the total cost is $51. for 3 pounds of chocolate chips and 5 pounds of walnuts, the total cost is $27. find the cost for each pound of chocolate chips and each pound of walnuts

Respuesta :

Yang100

Answer:

The cost for each pound of chocolate chips is $2.75 and the cost for each pound of walnuts is $3.75.

Step-by-step explanation:

9x+7y=51

3x+5y=27

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9x+7y=51

-3(3x+5y)=-3(27)

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9x+7y=51

-9x-15y=-81

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-8y=-30

8y=30

y=30/8

simplify,

y=15/4

9x+7(15/4)=51

9x+105/4=51

9x=51-105/4

9x=(204-105)/4

9x=99/4

x=(99/4)/9

x=(99/4)(1/9)=99/36

simplify

x=2.75

So the cost for each pound of chocolate chips is $2.75 and the cost for each pound of walnuts is $3.75.

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