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entrique uses a gift card to buy coffee at a coffee shop. The initial value of the guft cord is $20. The function n=20-2.75c represents the amount of money still left on the guft card n after c cups of coffee are bought. Find the zero of this function. Describe what this means in context.

1 Answer

4 votes

Answer:

7 cups of coffee

Explanation:

Given


n = 20 - 2.75c

Required

Find and describe the zero of the function

To do this, we simply equate n to 0

i.e.


n = 0

Substitute 0 for n in
n = 20 - 2.75c


0 = 20 - 2.75c

Add 2.75c to both sides


0 + 2.75c = 20 - 2.75c + 2.75c


0 + 2.75c = 20


2.75c = 20

Divide both sides by 2.75


(2.75c)/(2.75) = (20)/(2.75)


c = (20)/(2.75)


c = 7.273


c = 7 --- Approximated

This implies that the maximum cups of coffees that can be bought is 7