Help please And the work needs to be shown please help

Hunter designs two flags for his adventure club. what is the length of the base, x, of the larger flag? enter your answer, as a decimal, in the box.

One expression below in undefined, and the other expression has a well defined value. which expression is undefined and explain why it has no value. which expression is defined? what is the value of that expression and how do you know? what is a different expression using a trig inverse function that is also undefined?

The perimeter of a rectangle is 42 inches. if the width of the rectangle is 6 inches, what is the length