- #1

opus

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## Homework Statement

Find the area, A, of a sector of a circle with a radius of 9 inches and a central angle of 30°.

## Homework Equations

$$Area~of~a~Sector:$$

$$A=\left( \frac 1 2 \right)r^2θ$$

## The Attempt at a Solution

[/B]

$$θ=30°$$

$$θ=30°\left( \frac π {180} \right)$$

$$θ=\left( \frac π 6 \right)$$

$$A=\left( \frac 1 2 \right)\left(9\right)^2\left(\frac π 6 \right)$$

$$A=\left( \frac {81π} {12} \right)$$

$$A≈21.2 in^2$$

My question:

I know that when you find the area of a space, it will be in ##units^2##. But I've always thought of it as a square- that is, one equal side multiplied by the other equal side obviously results in a squared result. However in this case, I don't see how the units for a sector of a circle are squared, as it doesn't seem like we're multiplying two things of equal value to each other.

So why is this result squared?