Hello,
1: 9n-3=21 ==>B
2: 3n+9=21 ==>A
3: 9n-3=21 ==>B
4: 3n-9=21 ==>C
I wish to have understood all those sentences.
Answer:4
Step-by-step explanation:
Simplify what you can which is 0.1m-1.3m
you end up getting -1.2m
Now do the other side of the equation which is 2.1-2.7 which is -4.8
Divide -4.8 by -1.2 to get m=4
To subtract vectors, you simply have to subtract correspondent coordinates.
So, if you have

the subtraction is simply

So, in your case, we have
