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## Pre-algebra

### Course: Pre-algebra>Unit 2

Lesson 1: Math patterns

# Math patterns: toothpicks

Sal explores a pattern of creating figures with toothpicks. Created by Sal Khan.

## Want to join the conversation?

• For the toothpick video.

He does 6+5(x-1) x= # of houses

Can you do...

x5+1

I think Sal did the other way as a representation of the toothpicks but both ways would work. Please answer. :)
• YES!You are right x5+1 does the same thing as 6+5(x-1) x= # of houses GOOD CATCH.
• Don't you just love khan acedemy
• well kinda but mostly no
• why is he using toothpicks for his town house
• Because he's just making an art piece. (Or he's too poor to buy wood, nails, cement, and the other building supplies.)
• I'm just wondering why he complicated the calculation. I tried calculating myself for 500 houses before him solving the problem and did it this way
500*5+1=2501. He gets the same but in a much complicated matter. Is there something else I'm missing here? Some other type of lesson?
• He was probably trying to make it more clear that the first house requires 6 sticks, the parenthesis are there to subtract the multiplier before multiplying it to the multiplicand.
• I do not get it...Can someone say which grade this is and also how I can understand?
• I really regret not paying attention in math when I was in grade school. Im a senior and knowing patterns would've helped me massive when I was doing series and sequences math
• The good thing is that it is never too late to learn. Now that you recognize the value in learning some of these earlier skills, learn them now. You may find them useful later in life.
• why didn't you just write 5T + 1? You needlessly made the equation more complex than it needed to be
.
• In math there is no right or wrong way, only right or wrong answer.