Divide and simplify completely. assume that no denominator equals zero. d^2-1/d^2-d divided by d - 1/d

First, you should factor both the numerator and the denominator. Since the numerator is the difference of two squares, that can be factored into (d-1)(d+1); for the denominator, you can factor out d to get d(d-1). From there, you can reduce both the numerator and denominator by (d-1) to get (d+1)/d. If you need to simplify it further, I believe you can simplify it to 1+(1/d). 

The first digit is in the middle school 100s place