Should be markdown, but if you have other options let me know and I'll tell you which it is. But if markdown is one of your choices, or if this is fill-in, it's markdown.
Answer:
n = 18
Step-by-step explanation:
when you are multiplying, you add the exponents. 2 + x = 20. so by using subtraction we find that x = 18.
Answer: y= 6x-4
Step-by-step explanation:
I wrote it in y=mx+b format. m is the slope and b is the y-intercept.
The slope is 6 because 12/2=6
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