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A photo finishing store charges customers a rate of

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$0.29 per photo to print pictures.

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For new customers, the store offers a

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one-time discount of $3.

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Write a function representing the amount that a new customer

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would have to pay to have x number of photos printed.

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So x is the number of photos printed.

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So just a regular customer would have to pay the number

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of photos times $0.29 a photo.

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So if we just said, let y be the amount that a customer

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would have to pay, a regular customer would have to pay x

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times $0.29 per photo.

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So we'd write 0.29-- we could put the dollar sign there if

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you want-- or 0.29-- we're assuming everything is

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dollars-- x.

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That's how much a regular customer would have to pay.

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But they're asking us a first time, a new customer.

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And they say that the new customer gets a one-time

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discount of $3.

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So a new customer will pay this minus $3.

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So this right here is pretty much a simplified version of a

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function that would describe what a new customer would pay.

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If you wanted to get fancy, this is a little bit

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inaccurate when the customer ordered less than 10 photos

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because, let's say the customer orders 10 photos.

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Then x is going to be 10 times $0.29 is $2.90 minus 3 is

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negative $0.10.

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The customer is not going to pay negative $0.10, which

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would be like the store paying them $0.10 for them to print

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10 photos, the customer's not going to pay anything.

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So what we could do if we wanted to make this a little

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bit fancier, we could say that a new customer would pay-- and

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then we can say that's y, so y is equal to 0.29x minus 3 if x

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is greater than 10, if the guy or the gal orders

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more than 10 photos.

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It's 0 otherwise.

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Then they don't pay anything.

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If it's less than 10 photos, they pay nothing.

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It's not like the store's going to pay them, because if

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you're less than 10, or 10 or less, actually, then this is

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going to become negative and we don't want a situation

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where it's negative.

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So they're either going to pay nothing, but if they get more

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than 10 photos, then they're going to pay based on this

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function right there.

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