SOLUTION: Three pens and two notebooks cost $10.05. Two pens and three notebooks cost $10.45. How much would two pens and two notebooks cost?

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Question 843415: Three pens and two notebooks cost $10.05. Two pens and three notebooks cost $10.45. How much would two pens and two notebooks cost?
Answer by LinnW(1048) About Me  (Show Source):
You can put this solution on YOUR website!
set p = price of pen
n = price of notebook
3p + 2n = 10.05
2p + 3n = 10.45
multiply top by 2 and bottom by -3
6p + 4n = 20.10
-6p -9n = -31.35
add equations
-5n = -11.25
divide each side by -5
n = 2.25
Substitute 2.25 for n in 3p + 2n = 10.05
3p + 2(2.25) = 10.05
3p + 4.50 = 10.05
add -4.50 to each side
3p = 5.55
p = 1.85