20 points

2 answers:

7 0

Answer: $2+0.15(x-15)\le 7$ which is choice C

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Explanation:

x = total number of minutes spent using the vacuum

If x is larger than 15, then x-15 represents the amount of time spent past the first 15 minutes. The machine will charge 15 cents per minute at this point. The machine will charge 0.15 dollars for (x-15) minutes. So 0.15*(x-15) dollars is charged on top of the $2 already spent for those first 15 minutes.

In total, the cost for Caroline is
T = 2+0.15(x-15)

This total must not be larger than $7. The total T can be equal to 7 or smaller than 7

So,
$T \le 7$
$2+0.15(x-15)\le 7$

blsea [12.9K]3 years ago

6 0

The answer I think is 2+7+0.15x_>15

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