Answer:

Step-by-step explanation:
<u>Area of a Circle</u>
A circle is a geometric shape where all the points on its circumference are at the same distance to a fixed point called center. The radius is the distance from the center to any point of the circumference.
The relation of the length of the circumference to the radius is an irrational number called pi (
).
Another interesting relation in a circle is the area it occupies in a 2D space. Being r the radius of the circle, the area is computed by the formula

The party hat has a radius of r= 3 inches. The area of the circular base is computed as follows


6) x= 2, angle = 90 degrees obviously
7) Im not sure on this one
8) x = 5
9) x = 1
I am not sure, but I think you are talking about the least square method