Adriano wants to get a new cell phone plan. Company A: $80 for a new phone in the monthly fee of $45 a month. Company B: she can keep her all sound and pay $85 a month. Find the number of months it will take for the total cost for both companies to be equal.

it will take 2 months.

Step-by-step explanation:

Let x represent the number of months it will take for the total cost for both companies to be equal.

Company A: $80 for a new phone and the monthly fee of $45 a month. This means that the total amount that Company A charges for x months would be

80 + 45x

Company B: she can keep her all sound and pay $85 a month. This means that the total amount that Company B charges for x months would be

85x

For the total cost for both companies to be equal, the number of months would be

80 + 45x = 85x

85x - 45x = 80

40x = 80

x = 80/40 = 2

answer: the proof is mentioned below.

step-by-step explanation:

since, given:   lines bc = ef

prove:   lines ac > ef

          statements                                           reason

1. bc=ef                                           1. given

2. ac= ab+bc                                 2. because b is the point between the  

                                                            line segment ac

3.   ac > bc                                       3. because if a line segment is equal to

                                                          the sum of two line segments then it is

                                                          always greater then each of these

                                                          individual line segments

4. ac > ef                                         4. by equality property.