Answer:
6x+21 (Maybe)
Are you doing the buddy method, how is your teacher wanting to do this, When you respond I might have the correct answer
(buddy method) Multiply the 2x and 7 by the 3 giving you 6x+21 and then that's it you cant do anything else but I don't know if that's how you're teacher wants it done.
Answer:
I'm not sure but I believe the correct answer is line L2.
Step-by-step explanation:
It seems to be closer to more points than the other lines.
If it is not L2, it must be L3.
Assuming that each marble can be picked with equal probability, we notice that there is a total of

marbles, of which 2 are red.
So, the probability of picking a red marble is

In fact, as in any other case of (finite) equidistribution, we used the formula

A geometric sequence is one that involves addition or subtraction. One example would be "In an auditorium, the 1st row has 25 seats. The 2nd has 30. The 3rd has 35. How many does the 4th have? Take the formula, x + 5. All you do is simply add 5.
An arithmetic sequence is one that involves multiplication or division. For example, "Jon receives 5 dollars each week. If he waits for 5 months, how much money will he have? Honestly, all you have to do is think about the formula. x * 5. x would be the number of weeks.
I know my answer is not as good as the verified one, but it is simpler and easier to understand. I apologize if it isn't good enough.