A Normal Distribution Problem

Okay, I'm not sure wether this is Basic or Advanced, but I am having trouble processing how to find the area in a standard normal distribuution.

Here is the textbook's basic example; the mean is **zero**, the standard deviation is **one**, and the z-score is **.75**. I understand that the equation is **Z=(X-mean)divided by standard deviation**, and that the back of the book says the answer is **.7734**, but I don't understand what I must put in the calculator to make this data into that answer.

Also, what if I knew the area, but not the z-score? What would I do then?

EDIT: Oh DUH, forgot. The area before the z-score.