Answer:
It takes 13 months for the second phone to be less expensive than the first phone.
Step-by-step explanation:
First phone: y = 100 + 55x
Second phone: y = 150 + 51x
(x = number of months, y = total cost)
Make a T-Chart.
First phone: Second phone:
<u> x | y </u> <u> x | y </u>
0 | 100 0 | 150
1 | 155 1 | 201
2 | 210 2 | 252
3 | 265 3 | 303
4 | 320 4 | 354
5 | 375 5 | 405
6 | 430 6 | 456
7 | 485 7 | 507
9 | 595 9 | 609
10 | 650 10 | 660
11 | 705 11 | 711
12 | 760 12 | 762
13 | 815 13 | 813
After 13 months, the second phone will have costed $2 less than the first phone, and the price of the second will continue to be lower than the first.
Given:
The function for size of a square frame is

where, x is the side length of the picture.
The function for the price in dollars for the frame is

To find:
The single function for the price of a picture with an edge length of x.
Solution:
We know that, for a picture with an edge length of x.
Size of a square frame = f(x)
Price in dollars for the frame = p(x)
Single function for the price of a picture with an edge length of x is

![[\because f(x)=x+2]](https://tex.z-dn.net/?f=%5B%5Cbecause%20f%28x%29%3Dx%2B2%5D)
![[\because p(x)=3x]](https://tex.z-dn.net/?f=%5B%5Cbecause%20p%28x%29%3D3x%5D)
Let the name of this function is c(x). So,

Therefore, the required function is
.
Answer: 35,000 · 0.87t
Step-by-step explanation: A coefficient is multiplying
Combine (subtract) 3n and 2n to get 1n or n. Then you have n -5n =10n add 5n to 10n to get 15n. divide the 15 from n and your answer is n=15