If a store offers a 40 percent discount on all products, which linear model will help us find the sale price of a product?

y = 0.6x

y = 0.4x

y = 0.5x

y = –0.5x

Question

If a store offers a 40 percent discount on all products, which linear model will help us find the sale price of a product?

y = 0.6x

y = 0.4x

y = 0.5x

y = –0.5x

anonymous · Answer

I like to use 100 dollars as a quick tester to make sure i did it right. 
100 with 40 percent off means it will cost 60 dollars right?
if x = 100(dollars) which one of those would get you to 60 dollars?