Answer: C)46 ft
Step-by-step explanation:
We know that the circumference of a circle can be calculated with this formula:
Where "r" is the radius of the circle.
Since John is putting a fence around his garden that is shaped like a half circle and a rectangle, then we can find how much fencing he needs by making this addition:
Where "l" is the lenght of the rectangle and "w" is the width of the rectangle.
Since we know that the radius of the circle is half its diameter, we can find "r". This is:
Then, substituting values (and using ), we get: