# To print his first novel, Shane can use a print-on-demand book printer or he can buy a printer. The book printer charges a setup fee of $150 plus$6 per copy of the book. The printer he would need costs $750, and it would cost$2 per copy to print the book. For how many copies are the costs the same?

Question
Linear equations and graphs
To print his first novel, Shane can use a print-on-demand book printer or he can buy a printer. The book printer charges a setup fee of $150 plus$6 per copy of the book. The printer he would need costs $750, and it would cost$2 per copy to print the book. For how many copies are the costs the same?

2021-01-03
Let y be the total cost and x be the number of copies so that:
total cost=setup cost/printer cost+cost per copy×number of copies
For the print-on-demand book printer,
y=150+6x(1)
If Shane decides to buy a printer,
y=750+3x(2)
For the costs to be the same, equate (1) and (2):
150+6x=750+3x
Solve for x:
150+3x=750
3x=600
x=200
So, the costs are the same for 200 copies of the book.

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