Step-by-step explanation:
Well if you dont understand something ask a teacher for help or study on a topic that you struggle with for example math try looking up different math questions and solving them or ask a teacher is you can have pratice questions or problems then show it to him/her so they can check to see if you are right. Hope that help unless you dont understand a certain question that I might have missed.
Answer:
10) - 45 degrees
12) 0 degrees
Step-by-step explanation:
10)
Find the x and y components that define the vector that joins C with D:
x-component: -4 - (-8) = - 4 + 8 = 4
y-component: 4 - 8 = -4
use the tangent function to find the angle
:

12)
Find the x and y components that define the vector that joins A with B:
x-component: 7 - 4 = 3
y-component: - 1 - (-1) = -1 + 1 = 0
use the tangent function to find the angle
:

I'm not sure what this means. If you have choices you should list them.
(1/2)*(1/4 + 1/6) is an example of what should be given. There are two ways to solve this.
1. Use the distributive property.
1/2*1/4 + 1/2* 1/6
1/8 + 1/12 Which can be added using the LCD of 24
3/24 + 2/24 = 5/24
Method 2
Add what is inside the brackets first.
1/2 ( 1/4 + 1/6)
1/2(3/12 + 2/12 = 5/12
Now multiply by 1/2
1/2(5/12) = 5*1/(12 * 2) = 5 / 24 Same answer.