SOLUTION: Pencils= one price Pens = another price 2pencils and 3 pens=.78 3pencils and 2 pens =.72 How much does 1 pencils cost?

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Question 667977: Pencils= one price
Pens = another price
2pencils and 3 pens=.78
3pencils and 2 pens =.72
How much does 1 pencils cost?
Answer by ReadingBoosters(3246) About Me  (Show Source):
You can put this solution on YOUR website!
Establish variables
x = pencils
y = pens
...
Given
2x+3y=.78
3x+2y=.72
...
Multiply the first equation by -3 and the second equation by 2
-3(2x+3y=.78)
2(3x+2y=.72)
to get
-6x + -9y = -2.34
6x+4y=1.44
...
Add them together
-6x + 6x + -9y + 4y = -2.34 + 1.44
...
Combine like terms
-5y = -.9
Divide both sides by -5
highlight_green%28y+=+.18%29 for the price of pens
...
Multiply the first equation by 2 and the second equation by -3
2(2x+3y=.78)
-3(3x+2y=.72)
...
to get
4x+6y=1.56
-9x-6y=2.16
...
Add them together
4x + -9x + 6y + -6y = 1.56 + -2.16
...
Combine like terms
-5x = .6
Divide both Sides by -5
highlight_green%28x+=+.12%29 for the price of pencils
...
Check
cartoon%28%0D%0A2%28.12%29+%2B+3%28.18%29%2C%0D%0A.24+%2B+.54%2C%0D%0A.78%29
cartoon%28%0D%0A3%28.12%29+%2B+2%28.18%29%2C%0D%0A.36+%2B+.36%2C%0D%0A.72%29
.....................
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