The movement of the ant illustrates the length of an arc
The measure of the central angle is 2.625 radians
The radius of the arc is given as:
[tex]r = 8[/tex]
The distance walked is given as:
[tex]L = 21[/tex]
The length of an arc is
[tex]L = r\theta[/tex]
So, we have:
[tex]21 = 8\theta[/tex]
Divide both sides by 8
[tex]\theta = \frac{21}{8}[/tex]
Divide
[tex]\theta = 2.625[/tex]
Hence, the measure of the central angle is 2.625 radians
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