A phone company offers two monthly plans. Plan A costs $25 plus an additional $0.07 for each minute of calls. Plan B costs $16 plus an additional $0.09 for each minute of calls. Q1: For what amount of calling do the two plans cost the same? Q2: What is the cost when the two plans cost the same?

1) For 450 minutes of calling the two plans cost the same.

2) The cost when the two plans cost the same is $56.5.

Step-by-step explanation:

The cost of both plans can be modeled by linear functions.

Plan A:

$25 plus an additional $0.07 for each minute of calls.

So, for t minutes of calls, the cost is:

Plan B:

$16 plus an additional $0.09 for each minute of calls.

So, for t minutes of calls, the cost is:

Q1: For what amount of calling do the two plans cost the same?

This is t for which:

For 450 minutes of calling the two plans cost the same.

Q2: What is the cost when the two plans cost the same?

This is A(450) or B(450), since they are the same.

The cost when the two plans cost the same is $56.5.

correct choice is b

step-by-step explanation:

when you calculate the average rate of change of a function, you are finding the slope of the secant line between the two points. for the function the average rate of change from point to point can be calculated as

to find the average rate of change from day 2 to day 10, note that at day 2, 8 houses were sold, so a(2,8) and at day 10, 2 houses were sold, so b(10,2). thus,