Question

Morgan needs gas for her jeep which gets 21 miles per gallon for gas mileage. when she stops at the gasstation she already has 7 gallons of gas in her tank. she buys more gas for $1.25 a gallon. find the number of miles that morgan can drive, (d)s, as a function of the amount she spends on gas,s. d(s)=____________

Answer 1

pleaseeee help me sweethearts =)

Answer 2

Aww :D just give me a sec

Answer 3

So it's a function...

Answer 4

yeah

Answer 5

For the first function, of distance, she already has 7 gallons of gas in her tank, and gets 21 miles per gallon. Therefore, she can drive 147 miles on the gas she already has.

Answer 6

Now, depending on how much gas she buy, she will have more gas in her tank.
She gets 21 miles per gallon, but you don't know how many gallons she bought.

Therefore, the function for the first one is:
y = 21x+147 for mileage

Answer 7

For the second one, she already has 7 gallons and it costs 1.25 per gallon, we know she already spent $8.75 on gas

Answer 8

Depending on how many gallons she buys next, which is $1.25 per gallon, she may have x amount of gallons. That would mean 1.25x

Altogether, the function for cost is:
y = 1.25x+8.75