Answer:
At most 38 text messages.
Step-by-step explanation:
Let x represent number of text message you send or receive.
We have been given that the cell phone plan charges $.13 for each text message you send or receive. So amount charged for sending or receiving x text messages would be .
We are also told that your cell phone plan cost $39.99 per month, so total cost of monthly bill would be .
Since you can spend at most $45, so total cost of x messages should be less than or equal to 45 as:
Therefore, you can send or receive at most 38 text messages.