Use the site called Desmos, it's a graphing calculator and should help you in all the ways you need. It isn't complex. Just put that equation in a box and it graphs it for you.
Answer:

Step-by-step explanation:

12.

13.

16.

is already in simplest form.
Question is not complete, so i have attached it.
Answer:
B: -2x² - 6x² - 6x + 3x + 3 + 2
Step-by-step explanation:
From the image attached, the given polynomial is;
3 - 6x - 2x² + 3x - 6x² + 2
For like terms to be next to each other, we have to rearrange it as follows;
-2x² - 6x² - 6x + 3x + 3 + 2
Like terms are x² and x, thus they are now arranged next to each other.
The only option that corresponds to our answer is option B
These | | simple mean absolute value. Absolute value is simply the number positive, for example, the absolute value of -3 is simply 3