Given:
A circle of radius r inscribed in a square.
To find:
The expression for the area of the shaded region.
Solution:
Area of a circle is:

Where, r is the radius of the circle.
Area of a square is:

Where, a is the side of the square.
A circle of radius r inscribed in a square. So, diameter of the circle is equal to the side of the square.

So, the area of the square is:


Now, the area of the shaded region is the difference between the area of the square and the area of the circle.




Therefore, the correct option is (a).
B
Two points is a line
One capital letter is the plane
Answer:
40 miles
Step-by-step explanation:
In the attached diagram, Point A is the starting point and C is the end point. We want to determine the distance from A to C.
The path driven forms a right triangle in which AC is the hypotenuse.
We therefore use the<u> Pythagorean Theorem</u> to solve for the AC.
Pythagorean Theorem: 

The straight line distance from the starting point is 40 miles.
Answer:
97
Step-by-step explanation:
83 and JKL form a straight line so they add to 180 degrees
83+ JKL = 180
Subtract 180 from each side
83-83+ JKL = 180-83
JKL = 97