Step-by-step explanation:
-3(-x -3y) = 3( x +3y) = 3x+9y
He's using the graduated cylinder method. I think the volume might be between 15 and 20. (It's kind of not obvious...)
Answer:
The distance between the two points is 
Step-by-step explanation:
In order to find the distance between two coordinate pairs, we can use the distance formula:

Our coordinate pairs need to be labeled accordingly, so we can use this naming system:

This assigns a name to our points:
Therefore, we can plug these into the formula and solve:

Therefore, the distance between the two points is
.
2-21x+28
-21x +3
Hope it helps