4: (3/4 - 1/2) X 3/5.
You need them all to have the same denominator (bottom number)
The lowest common denominator (LCM) of 2,4 and 5 is 20
4 X 5 = 20
2 X 10 = 20
5 X 4 = 20
Then multiply the top number by the amount you need to multiply the bottom number by to get 20
3 X 5 = 15
1 X 10 = 10
3 X 4 = 12
(3/4 - 1/2) X 3/5. Turns to (15/20 - 10/20) X 12/20.
15 - 10 = 5
5 X 12 = 60
Answer: 60/20
Simplified: Either 3 or 3/1.
If you use the steps above then you should be able to do the rest :D
If you need anymore help, please ask
Answer:

Step-by-step explanation:

Answer: 17
Step-by-step explanation: ok so first to find the mean you add all the numbers then divide by how many numbers there is so basically 18 plus 15 plus 20 plus 15 then divide by 4 because there is 4 numbers and once you do that it is 17
The slope of a vertical line is undefined, D.
If you were to try to solve use something like the rise over run method, you would end up with a 0 in the denominator. Since dividing by 0 gives you an undefined result, the slope would be undefined.