Question

You drive a car that holds 15 gallons of gasoline. Your car uses 0.03 gal per mi. Which equation
best represents this information.

A.y = 0.03x + 15 B.y = 0.03x - 15 C.y = -0.03x + 15 D.y = -0.03x - 15

Answer 1

i think im trying to over think this but in my mind it should be y=0.03x divided by 15

Answer 2

but with those the closest would be y= 0.03x-15

Answer 3

There is no such thing as the closest. You have a initial amount: 15
Then this amount decreases at a rate of 0.03 per mi. When t=x=0, it must be 15, because this is the initial instant.
So everything that has -15 is wrong.
Then we look at the other term. When x gets greater, the total amount must decrease, so it is negative. Now the only option left is C