Your parents allow you to borrow a car to get to your part-time job, but you have to pay for a tank of gas each month. gasoline costs $2.76/gallon and the tank takes 15 gallons. you have 2 coworkers who are each willing to pay for a quarter of a tank each month to carpool with you to work. how much do you save each month? $20.70 $16.46 $18.55 $15.91

Let’s keep in mind that gas is $2.76 a gallon.
2 friends each pay 1/4 of a gallon. 1/4 times 2 is 1/2. This means for a full tank (15 gallons) your only paying for half.
What is half of 15 gallons? Divide 15 by 2. That should give you 7.5 gallons. You are only paying for 7.5 gallons of gas.
You are paying for a full tank every month, according to the beginning of this paragraph. But don’t worry, your coworkers gotcha covered. You only have to pay for 7.5 gallons.
So if a gallon of gas costs us $2.76, how much will 7.5 gallons cost us?
Let’s multiply the cost of 1 gallon with the number of gallons we want (7.5).
$2.76 times 7.5 will give us $20.70.
This is how much money you have to pay. Now let’s find out how much your saving off your coworkers.
They are paying for the same amount you are, since it’s half the gas. So they are also paying $20.70.
That means you’re saving half the money for a full tank.
You’re saving $20.70.
Hope it helps <3

Do you need with the x value for the minimum? its always between the two intercepts for a parabola