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3 years ago

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A store charges their customers based on the number of items that they buy. Jane bought four items and was charged $15 and Georg

e bought twelve items and was charged $39. Write a function to model the cost based on the number of items you buy. Then determine how much you bought if you were charged $33.
A) f(x) = 3x + 3; f(10) = 33
B) f(x) = 3x + 3; f(33) = 102
C) f(x) =1/3 + 3; f(90) = 33
D) f(x) = 1/3x + 3; f(33) = 14

1 answer:

mojhsa [17]3 years ago

7 0

Answer:

A) $f(x) = 3x + 3; f(10) = 33$

Step-by-step explanation:

$39 = 3x + 3 \\ \\ 36 = 3x \\ \\ 12 = x$

$15 = 3x + 3 \\ \\ 12 = 3x \\ \\ 4 = x$

* $33 = 3x + 3 \\ \\ 30 = 3x \\ \\ 10 = x$

** From what the problem said, we know that we selected the correct equation.

I am joyous to assist you anytime.

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