Option E
The person used the phone for 20 minutes that month
<em><u>Solution:</u></em>
Given that phone company charges customers a monthly charge using the equation:
C = 40 + 0.3m
Where,
"C" is the monthly charge in dollars
"m" is the number of minutes used by the customer
Someone's monthly charge is $46
To find: number of minutes used by that person
Therefore, given C = 46
Substitute C = 46 in given equation
46 = 40 + 0.3m
40 + 0.3m = 46
0.3m = 46 - 40
0.3m = 6
![m = \frac{6}{0.3} = 20](https://tex.z-dn.net/?f=m%20%3D%20%5Cfrac%7B6%7D%7B0.3%7D%20%3D%2020)
Thus the person used the phone for 20 minutes that month