First example:
Subtract the 8n on both sides to get the variable on one side of the equation. Do the same for the regular numbers. Then divide by -3.

This should be your final answer.
Second Example:
Do the same thing as explained in Example 1. Here's some work to help guide you.

That should be your final answer here.
Third Example:

Hope this helps and its understandable! Let me know if you still don't understand.
Answer:
Step-by-step explanation:
AB=-4-(-6)=2
DC=-4-(-6)=2
BC=-2-(-4)=2
AD=-2-(-4)=2
Perimeter=4*2=8 units
Answer:
48%
Step-by-step explanation:
48 out of 100 = 48%
:D
Answer:
19.14lb
Step-by-step explanation: