# How do you find the lengths of the arc on a circle of radius 9 feet intercepted by the central angle #60^circ#?

##### 1 Answer

Use the arc length formula (see below)!

#### Explanation:

For this particular problem (with units in mind), the formula for arc length is

Where

You don't really have to work too hard to remember this formula. The arc length formula is easy to remember because it is just the circumference of the circle times the central angle over

Anyway, let's continue with the problem. We are given that the central angle is *feet*:

Now, you might be tempted to plug this in your calculator, but let's simplify it a little bit more.

So, if you wanted an exact answer, it would be that the arc length is

I hope that helps!