Marco has a $15.00 gift card to a movie theater. He wants to buy each of his friends a $3
candy bar. The function f(x)=3x-15 represents the amount of cash needed to purchase x candy
bars after using his gift card. He brings 7 friends. How much of his own money does he need
to spend to buy all 7 friends a candy bar?

Respuesta :

Answer:

I believe the answer is 6

Step-by-step explanation:

f(x) = 3x - 15 -- plug 7 into x (that's how many candy bars he's buying)

f(x) = 3(7) - 15 -- solve the equation (just know that 3(7) is the total, and 15 is the amount of money on his gift card.)

f(x) = 21 - 15

f(x) = 6 -- your answer

I hope this helps :)