In circle H with m/GHJ = 66 and GH = 10 units, find the length of arc GJ.

Round to the nearest hundredth.
G
H

3 answers

J

We use the formula for the length of an arc of a circle:

Length of arc = (central angle/360 degrees) x 2πr

In this case, the central angle is m/GHJ = 66 degrees, and the radius of the circle is half the diameter GH = 5 units.

So,

Length of arc GJ = (66/360) x 2π(5)

Length of arc GJ = (11/60)π(5)

Length of arc GJ ≈ 2.89 units

Rounded to the nearest hundredth, the length of arc GJ is 2.89 units.
GH is clearly not the diameter, but is the radius, since H is the center of the circle. So the radius is 10, not 5. So GJ=5.78.
You are correct, I apologize for the error. If GH is the radius of the circle and is equal to 10 units, then the diameter of the circle is 20 units. The central angle m/GHJ is 66 degrees, which is approximately 0.1833 radians (since 180 degrees equals π radians). Therefore, the length of arc GJ is:

Length of arc GJ = (central angle/2π) x circumference of the circle
Length of arc GJ = (0.1833/2π) x 20π
Length of arc GJ ≈ 5.78 units

Rounded to the nearest hundredth, the length of arc GJ is 5.78 units. Thank you for bringing this to my attention.