a
Undefined
b
Negative
c
Zero
d
Positive

A, undefined

Step-by-step explanation:

The general rule is that vertical lines are undefined slope, because there's literally no change in x values. The vertical line test also fails, meaning there is no slope. Horizontal lines have a slope of 0, while vertical lines don't own any numbers that are important except for x-axis numbers.

If you do y2-y1 over x2-x1, you literally get 1/0 which is nothing. 0/1 = 0, but 1/0 is nothing.

Hope this helps!

1. 8

2. 9

3. 20

4. 3

5. 17

6. 2.2

7. 11.25

8. 1

9. 14

10. 2

step-by-step explanation:

thats the first half

relating to or denoting a system of numbers and arithmetic based on the number ten, tenth parts, and powers of ten.

it alot will look like this 4.4