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The cost of five pencils and one pen is 2.50$, and the cost of one pencil and two pens is 1.85$. What is the cost of two pencils and one pen?

Respuesta :

jorel1380
Let pc be pencils, and pn be pens. Then:
5pc+pn=250
pc+2pn=185
Then
10pc+2pn=500
pc+2pn=185
9pc=315
pc=35
pn=75
Pencils are 35 cents; pens are 75 cents

Answer:

5.50

Step-by-step explanation:

make two equations:[tex]x + y = 2.50[/tex]

and [tex]2x + 3y = 5.50[/tex]

we can multiply the top equation by -2

-2x   - 2y  = 5.00

 2x  + 3y  = 5.50

+

---------------------

          [tex]y = .50[/tex]

We can plug y into the first to get [tex]x + .50 = 2.50[/tex]

add them up to get  5.50

Hope this helps :)

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