Anyone, in the world, can ask or answer questions. If you posted a question that has not been answered, here are a few possible reasons:
1.) If it appears you are posting most of your assignment, it probably will not get answered. This site is for explaining / tutoring purposes, not doing your homework for you.
2.) You need to give it enough time. This is not a calculator. It may not be answered within seconds or minutes. If it relates directly to this site, it will probably be answered and explained thoroughly, but it may take some time. Relax! Do something else, and stop back later!
3.) Your question may not be relative to this site. Most people using this site are involved with Basic Math, Pre-Algebra, Algebra 1, Algebra 2, Geometry, and College Algebra. If you are asking Calculus, Chemistry, or Physics questions, they probably will not get answered.