Answer:
125 text messages.
Explanation:
Let x represent number of text messages.
We have been given that the Call First cell phone company charges $35 per month and an additional $0.16 for each text message sent during the month.
The cost of sending x text messages using call first would be
.
The total cost of sending x text messages using call first would be
.
Cellular Plus, charges $45 per month and an additional $0.08 for each text message sent during the month.
The cost of sending x text messages using cellular plus would be
.
The total cost of sending x text messages using cellular plus would be
.
Now, we will equate both expressions to solve for x as:
![0.16x+35=0.08x+45](https://img.qammunity.org/2020/formulas/mathematics/college/99bso2c095qi2xlvvl3kix62rxviqhr6ir.png)
![0.16x-0.08x+35=0.08x-0.08x+45](https://img.qammunity.org/2020/formulas/mathematics/college/a5tobzaphtsbn6j8mt9fcq66rrbeayv4ly.png)
![0.08x+35=45](https://img.qammunity.org/2020/formulas/mathematics/college/8lzz2wu4nonnnxoqubcfp1uyyjm0yqj7es.png)
![0.08x+35-35=45-35](https://img.qammunity.org/2020/formulas/mathematics/college/6pqe9tz7athm88zszf5aweq347807af58x.png)
![0.08x=10](https://img.qammunity.org/2020/formulas/mathematics/college/zlbj8d4y69soqxgdeevbxf2jxh88zcqmrf.png)
![(0.08x)/(0.08)=(10)/(0.08)](https://img.qammunity.org/2020/formulas/mathematics/college/wru6m1ltr7uqj6vfzztio28a2fd7130k21.png)
![x=125](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ebd169yqaejp2baqjfwc0blfpqesyxn586.png)
Therefore, 125 text messages would have to be sent in a month to make both plans cost the same.