Answer: 4 dollars for each notebook
Step-by-step explanation:
21-9= 12
12/3=4
each notebooks costs 4 dollars
189 because 20.7 rounds to 21 and 9.18 rounds to 9
21 * 9 = 189
Answer:
2 inches
Step-by-step explanation:
If the long side is 6 inches and it's 3x the length of the short side, then you need to divide the long side into 3 parts because the short side is 1/3 the length of the long side. This means that the short side is 2 inches.
LORAN follows an hyperbolic path.
The equation of the hyperbola is: 
The coordinates are given as:

The center of the hyperbola is

The distance from the center to the focal points is given as:

Square both sides

The distance from the receiver to the transmitters is given as:

Divide both sides by 2

Square both sides

We have:

This gives

The equation of an hyperbola is:

So, we have:


Hence, the equation of the hyperbola is: 
Read more about hyperbolas at:
brainly.com/question/15697124