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- [Voiceover] What is
the area of the figure?
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So down here we have this one, two, three,
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four, five, six, seven,
eight, nine, 10-sided figure,
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and we want to know its area,
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how many square meters
does this figure cover?
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And we have some measurements,
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that seems helpful,
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but what's not too helpful to me is
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I don't know the special trick
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to find the area of a 10-sided figure
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so I've got to think about what I do know
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and what I do know
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is the way to find area of a rectangle.
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So what I can do, because I can see,
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if I can find any rectangles in here.
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Here's one rectangle, right there.
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So I can find the area of that part.
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Then let's see if I can find any more.
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Here's another rectangle.
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So I can find the area of that part.
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We could call that one
a rectangle or a square.
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And then that leaves
us with this last part,
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which is again, a rectangle.
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So what we did is, we broke this up
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or decomposed it into three rectangles
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and now if I find out how much space
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this purple one covers,
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and the blue one and the green one,
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if I combine those, that
would tell me the area
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of the entire figure,
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how much space the entire figure covers.
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So let's start with this one right here.
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This one is three meters long,
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so we can kind of divide
that by three meters,
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into three equal meters,
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and then we've got a width
of two meters down here
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so we can split that in half.
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So if we draw those lines out,
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we can see this top row is
going to cover one square meter,
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two square meters, three square meters,
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and then there's two rows of that,
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so there's two rows
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of three square meters
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for a total of six square meters.
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This rectangle covers six square meters,
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so this part of the entire figure
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covers six square meters.
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The next one, our measurements
are three and a three,
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so it will have three rows
of three square meters
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or nine square meters,
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and then finally this purple one
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has three meters and nine,
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so we can say it will
have three rows of nine
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or nine rows of three square meters
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which is 27 square meters.
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So the area
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of this purple section,
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it covers completely 27 square meters.
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The green covers nine square meters,
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and the blue covered six square meters.
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So, if we combine all those areas,
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all those square meters it covers,
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that will tell us the
area of the entire figure.
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So we have six square meters,
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plus nine square meters,
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plus 27,
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and we can solve that,
six plus nine is 15,
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15 plus 27, let's see,
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five ones and seven ones
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is 12 ones.
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We'll just find some space up there.
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And
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one 10 and two 10's
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or a 10 and a 20
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is 30.
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And 30 plus 12 is 42.
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So the area of the entire figure is
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42
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square
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meters.