Question

Cell Phone Company A charges $20 each month plus $0.03 per text. Cell Phone Company B charges $5 each month plus $0.07 per text. Write a system of equations to model the situation using c for cost and t for number of texts. How many texts does a person need to send in a month to make the costs from both companies equal?

Answer 1

20 + 0.03t = 5 + 0.07t

Answer 2

Answer: The cost from company A $C(t)=20+0.03t$

And  the cost from company B $C(t)=5+0.07t$

The number of a person need to send in a month to make the costs from both companies equal=3,750

Step-by-step explanation:

Let 't' be the number of text in a month.

Therefore, the cost from company A $C(t)=20+0.03t$

And  the cost from company B $C(t)=5+0.07t$

To find the number of text a person need to send in a month such that the costs from both companies equal, we need to equate the above functions.

$20+0.003t=5+0.007t\\\Rightarrow0.007t-0.003t=20-5\\\Rightarrow0.004t=15\\\Rightarrow\ t=\frac{15}{0.004}\\\Rightarrow\ t=3,750$

Hence, the number of a person need to send in a month to make the costs from both companies equal=3,750