Answer:
≈ 18.8 cm
Step-by-step explanation:
The arc length is calculated as
arc = circumference of circle × fraction of circle
The central angle is equal to the arc subtending it, that is 60°
arc = 2πr ×
= 2π × 18 ×
= 36π ×
= 6π ≈ 18.8 cm ( to 1 dec. place )
<u>Given</u>:
Given that the measure of ∠CDR = 85°
We need to determine the measure of and
<u>Measure of arc RC:</u>
Since, we know that if a central angle is formed by two radii of the circle then the central angle is equal to the intercepted arc.
Thus, we have;
Substituting the values, we get;
Thus, the measure of is 85°
<u>Measure of arc CBR:</u>
We know that 360° forms a full circle and to determine the measure of arc CBR, let us subtract the values 360 and 85.
Thus, we have;
Substituting the values, we have;
Thus, the measure of is 275°