Questions: Find the radian measure of the central angle θ given the radius r and the arc-length s transcribed by θ.
r=10 in.; s=21 in.
Transcript text: Find the radian measure of the central angle $\theta$ given the radius $r$ and the arc-length $s$ transcribed by $\theta$.
\[
r=10 \text { in.; } s=21 \text { in. }
\]
Solution
Solution Steps
Step 1: Identify the given values
The problem provides the radius \( r = 10 \) inches and the arc length \( s = 21 \) inches.
Step 2: Use the formula for the central angle in radians
The formula to find the central angle \( \theta \) in radians is:
\[ \theta = \frac{s}{r} \]
Step 3: Substitute the given values into the formula
Substitute \( s = 21 \) inches and \( r = 10 \) inches into the formula:
\[ \theta = \frac{21}{10} \]