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Daniel brought a total of 39 pens and pencils and he spent a total of $91. If pencils cost two dollars each and pens cost three dollars each how many of each did he buy

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Sarah06109

Answer:

26 pencils and 13 pens

Step-by-step explanation:

First, define the variables. Lets say x represents pens and y represents pencils.

Next, make 2 equations with the information provided.

2y+3x=91

y+x=39

Then, multiply the second equation by 2 so a variable (y)  can be canceled out.  

2y+3x=91

2y+2x=78

Subtract the 2 equations

x=13

Next, substitute 13 in for x in the second equation.

y+x=39

y+13=39

Subtract 13 from both sides, and y=26

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