Here's the word problem:

Question

You have a coupon for $50 off your camera purchase of $100 or more at Camera World.

Write a function relating a camera's purchase price after coupon, y, to the retail price, x.
Give the domain of this function.

Here is what I have so far:

y = price after coupon x = original price

x - y >= 100 NOTE: >= is "greater than or equal to".

I don't think I wrote the function correctly. Also, I can't seem to remember what the "domain of a function" is.

Any help you could provide is very much appreciated.

Answer 1

y = x - 50
domain x>100

domain is the part of the x axis where the function is valid

for example the function
y = 1/x
domain is 0< x <0
but does not include x = 0
where it is undefined