5 times a number is 14 less than the square of that number. Find the positive solution.

The first-serve percentage of a tennis player in a match is normally distributed with a standard deviation of 4.3%. if a sample of 15 random matches of the player is taken, the mean first-serve percentage is found to be 26.4%. what is the margin of error of the sample mean? a. 0.086% b. 0.533% c. 1.11% d. 2.22%

I’m stuck on this equation, anyone got the answer?

Typically a point in a three dimensional cartesian coordinate system is represented by which of the following answers in the picture !