Question 1129203
I am assuming that company 2 is $20 per month
Let t stand for the number of texts sent
An expression for 1 month with company 1: 15+.05t
An expression for 1 month with company 2: 20
An expression for 1 month with company 3: 3+.10t
company 1= 15+7.5= 22.5
company 2= 20 =20
company 3= 3+15 =18

So for 150 texts per month, company 3 would have the best offer