The elves and reindeer are getting ready for a meeting with
Santa. 15 of them have arrived
so far. If they have 40 legs
between them, how many elves
are at the meeting and how
many reindeer are at the
meeting?
G

Step-by-step explanation:

Let the number of elves be x and reindeer be y, then we have equations:

Simplify the second equation and subtract the first one:

Then find x:

10 elves and 5 reindeer at the meeting

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'.