Question

Need help please (: have no idea what to do

Answer 1

Here's what you must do in order to answer this question in the picture:

Step #1:
Either open a book or go on line, and find out what in the world
the "transverse axis of a hyperbola" is.

I did that just now.  This much effort should be enough to earn me
5 points, but it's not too helpful to you if I don't use my new-found
knowledge to help you answer the question.

On line, on the site that  rhymes with Floogle, I searched for "transverse
axis of a hyperbola", and after about 0.3 seconds, I got so many hits that
it felt like I was in a paint-ball fight.  I learned that the transverse axis of
a hyperbola is the line segment that joins the vertices of the hyperbola's
two parts ... the line between their 'noses'.  I never knew that.

Step #2:
In order to find the length of the transverse axis, you'll need to know
the distance between the noses.  This requires looking at the picture.
In this particular picture, the noses are on the x-axis, at the points
x=9  and  x=-9 .
The distance between them is  18 .

Step #3:
Take the distance you found by looking at the picture, and substitute
it in the definition of the transverse axis:

Definition:

     Length of transverse axis of a hyperbola = Distance between the noses.

Substitution: 

     Length of transverse axis of THIS hyperbola  =  18 .

You may have noticed that in the process of guiding you to the answer,
I hacked the phrase 'transverse axis' and its definition to death, hammering
on it as if I were a blacksmith tempering a horseshoe.  I did that so that after
typing it so many times, and reading it so many times, you and I will both
remember what it means.