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Two-Step Equations using Addition and Subtraction, a la Shmoop.

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Darlo is your average foreign exchange student.

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He hails from a country no one can pronounce, dresses like it's 1978, and is hopelessly

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in love with the wrong girl. In a desperate effort to win McKenzie's heart,

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Darlo enters the Spring Talent Show.

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Unfortunately his only talent is disco...and the ability to grow more chest hair than a

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gorilla in a leisure suit. Darlo boogies away for three rounds of the

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tune "Disco Love" and six minutes of "Dance Fever."

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If Darlo continues these dance moves for exactly ten minutes before getting annihilated by

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McKenzie's boyfriend...

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...can you determine how long the song "Disco Love" is?

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First we'll need to find the variable. Since we want to solve for Disco Love's length,

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we'll call that x. Darlo dances "Disco Love" three times, so

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we'll write 3x.

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Now we'll add the six minutes he grooves to "Dance Fever."

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Darlo dances for a total of 10 minutes. So 3x + 6 = 10

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Like bad polyester, there is a whole bunch of stuff we don't need in order to solve for

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x.

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To get all the x's on one side, we can subtract 6 from both sides to get 3x equals 4.

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Remember to make the same move on both sides of that equal sign to maintain equality.

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To solve for x, divide both sides by 3. 3x divided by 3 equals x... so there you have

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it! x equals four thirds.

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This means that "Disco Love" is four-thirds minutes long...

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...which, in English, is one minute and twenty seconds too long.

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And one more thing.

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Darlo, next time you fall for a girl, make sure her boyfriend isn't on the football team.

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And the basketball team.

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And the soccer team.

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