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Solving Two-Step Equations Using Addition and Subtraction 10212 Views


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Description:

Solving two-step equations can be tricky, but at least they’re easier than doing the Texas Two-Step. We trip over our feet so often you’d think we were a centipede.

Language:
English Language

Transcript

00:04

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

00:10

Darlo is your average foreign exchange student.

00:12

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

00:18

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

00:27

Darlo enters the Spring Talent Show.

00:30

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

00:35

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

00:41

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

00:45

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

00:49

McKenzie's boyfriend...

00:50

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

00:54

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

01:00

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

01:05

we'll write 3x.

01:07

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

01:12

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

01:19

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

01:24

x.

01:24

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

01:38

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

01:43

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

01:52

it! x equals four thirds.

01:55

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

01:59

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

02:04

And one more thing.

02:05

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

02:18

And the basketball team.

02:19

And the soccer team.

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