Question

The circular opening of a tunnel

has a circumference of 42
meters. Which equation can be
used to find d, the diameter of
the tunnel opening?

Answer 1

2(21/pi)=d

Step-by-step explanation:

The formula for a circumference is C=2(pi)(r) in this case we know our circumference is 42 meters so 42=2(pi)(r), we must leave our radius by itself so we divide by 2 to get 21=pi(r) we then also divide by pi which will get us 21/pi=r and we know that the diameter is double of the radius so we just double which will then be 2(21/pi)=d