sand dollar. n. 1. Any of various thin circular echinoderms of the order Clypeasteroida, especially Echinarachnius parma, of coastal northern Atlantic and Pacific waters, having a covering of short movable spines.
One reason why linear algebra is very useful is that linear transforms of normal variables are normal. If x ~ N(a, A), then Bx+b ~ N(Ba+b, BABT). In a way, when everything is linear and normal, everything is nice and analytically tractable.
Regardless of the technology though Gaussian elimination still proves to be the best way known to solve a system of linear equations (Tucker, 1993). The influence of Linear Algebra in the mathematical world is spread wide because it provides an important base to many of the principles and practices.