ShmoopTube

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Here's your shmoop du jour...

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The sin of angle A equals 4/9. What is the length of side B?

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And here are your options...

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We know that the sin of an angle equals the opposite side divided by the hypotenuse. Here,

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the sin of A equals 4/9, which means that a = 4 and c = 9. Now we just need to find B

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We can do that by using the Pythagorean theorem...which

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is A squared plus B squared equals C squared. We plug the values in, and get that 4 squared

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plus B squared equals 9 squared. 16 plus B squared equals 81.

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Subtract 16 from both sides, and we get that B squared equals 65.

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Take the square root of both sides, and we have that B equals the square root of 65.

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Which is answer choice C.

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Easy.

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