ShmoopTube

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For a good time solve this shmoopy question...

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What is the measure of angle ABC if line

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AC measures 2pi, B is the center, and line BC measures 4?

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Here are the potential answers...

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Here's angle ABC. This arc AC

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is 2pi and line BC right here

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is 4. We also know that circle problems are gonna test us on

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two basic formula usually. Area

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which is pi r squared and circumference which is 2

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pi r. We've been told that line BC is a radius

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so let's plug it in to solve for circumferance

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since line BC is 4 is for we know that 2

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pi 4 is just 8pi. They give us

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that this arc is 2 pi so what's 2

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pi over 8pi? Yeah, it's 1/4 and

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all the way around the clock is 360 degrees. 1/4 of the way around the clock

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is from midnight to 3

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recognize anything special about this little angle here?

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Yeah. It's right!

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This right. Yeah ninety degrees. It's E.

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