What does (-9)^-2 mean?

Subtract 8 1/6 - 4 5/6 . simplify the answer and write as a mixed number.

Can you simplify 4/7? 24 points will be awarded!

There is an entrance to the computer room at point e which lies on ab and is 5 feet from point a. plot point e on the coordinate plane. find the distance from the entrance at point e to the printer at point e