What is the difference in height between an albatross flying at 100 m above the surface of the ocean and a shark swimming 30 m below the surface?

 130 meters

Step-by-step explanation:

We have to let the "surface of the ocean" be at 0 height.

So,

anything above surface has POSITIVE height

and anything below surface has NEGATIVE height

The albatross is 100 m above, so we can say its height is:

+100 meters

The shark is 30 m below, so we can say its height is:

-30 meters

The difference in height is thus:

100 - (-30) = 100 + 30 = 130 meters

for the friend request.

when a figure, such as triangle (xyz) is reflected over the line y = x to create x'y'z' the x-coordinates and y-coordinates of the original image (pre-image) will be reversed for the image. (e.g., (x, y) > (y, x)) this means that the pre-image position of the x- and y-coordinates switch places which in turn provides a mirror like image of the original xyz.  

i notice that when i draw a line segment from x to x', that the points are parallel from each other -- they are exactly across from each other and do not intersect with any other points.  

yes, think i would see the same characteristic if you drew the line segment connecting y with the reflecting line and then y' with the reflecting line because of the essence of reflections. because it is a mirror image, each point was effected the same way which leads me to conclude that they same would apply to y and y'.