Answer:
i am unsure aswell please let me know.
Step-by-step explanation:
Using the fundamental counting theorem, we have that:
- 648 different area codes are possible with this rule.
- There are 6,480,000,000 possible 10-digit phone numbers.
- The amount of possible phone numbers is greater than 400,000,000, thus, there are enough possible phone numbers.
The fundamental counting principle states that if there are p ways to do a thing, and q ways to do another thing, and these two things are independent, there are ways to do both things.
For the area code:
- 8 options for the first digit.
- 9 options for the second and third.
Thus:

648 different area codes are possible with this rule.
For the number of 10-digit phone numbers:
- 7 digits, each with 10 options.
- 648 different area codes.
Then

There are 6,480,000,000 possible 10-digit phone numbers.
The amount of possible phone numbers is greater than 400,000,000, thus, there are enough possible phone numbers.
A similar problem is given at brainly.com/question/24067651
Answer:
{10,8}
Step-by-step explanation:
-3x + 4y = -62
4x + 5y = 0
let's eliminate the x
-3x + 4y = -62 | x -4 |
4x + 5y = 0 | x 3 |
12x - 16y = 248
12x + 15y = 0
-------------------- -
-31y = 248
y = 248/(-31) = 8
since you must do this proble with elimination, we cant use subtitution. so we repeat the way once more to find x (eliminate y)
-3x + 4y = -62 | x 5 |
4x + 5y = 0 | x 4 |
-15x + 20y = -310
16x + 20y = 0
-------------------- -
-31x = -310
x = -310/-31 = 10
Odd integers between 8 and 26
{ 9,11,13,15,17,19,21,23,25}...added = 153 <==