johniquerobinso johniquerobinso
  • 02-06-2017
  • Mathematics
contestada

phillip bought 12 used cds and dvds.cds cost $2 each,and dvds cost $3 each.he spent $31,not including tax.how many dvds did phillip buy?

Respuesta :

irspow
irspow irspow
  • 02-06-2017
Let c and d be the number of cds and dvds respectively.

c+d=12

c=12-d

The we are told that:

2c+3d=31, using c found above in this equation gives you:

2(12-d)+3d=31

24-2d+3d=31  

24+d=31

d=7

So Phillip bought 7 dvds.

check...

3*7+2(12-7)=31

21+2(5)=31

21+10=31

31=31
Answer Link
zame
zame zame
  • 06-02-2021

Answer:

he bought 7 dvds

Step-by-step explanation:

Answer Link

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