ShmoopTube

00:02

Buckle up! It's question time.

00:05

When you square a certain number, the result is equal to ten times the number plus the number again.

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What is the number?

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Another equation given to us in words that we have to translate to numbers…

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Let’s call the number we’re looking for x.

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Squaring x gives us x squared… …which equals ten times the number…

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10x…plus the number again…so PLUS x.

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We can write this as the equation x squared equals 11x.

00:34

What number squared equals 11 times that number?

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We can solve the problem with a little logic. Well…it must be 11…

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See how it works. 11 times 11 is 121. 11 squared is 121 and they equal each other.

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If we weren’t sure though, x squared is the same as x times x…

00:53

…so we can simply divide x from both sides. The correct answer is 11 and we're done!

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