Solve for the variable please help

The mean of a set of data is -3.82 and its standard deviation is 2.31. find the z score for a value of 3.99.

(50 points) drag each description to the correct location on the table. each description can be used more than once. some systems of equations and their graphs are given in the table. for each system, place the description(s) in the box that correctly describe the type of system shown. :

What number should be added by both sides of the equation to complete the the square? x^2-10x=7