WEBVTT
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Here we have Ann trying to find
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the length of a support line that
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she would need to tie to this radio tower.
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When you see things like flag poles,
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radio towers, people,
these things all stand up
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straight and usually they
form right triangles.
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So, not always, but quite
typically when you see
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these types of setup,
you're really looking at a
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Pythagorean theorem question and
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that's what we have here.
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So, let's draw it out.
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Here we have the radio
tower and here's the ground.
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We know that the radio
tower is 50 feet tall
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and we know that the anchor spot,
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where Ann wants to tie the line,
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is about 30 feet from the towers base.
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And here's Ann's support line.
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So, we want to find the length of
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that support line.
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As you can see, we have a right triangle.
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That's a right angle there.
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Anytime you have a right triangle
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and you know the lengths
of two of its sides
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you can find the length of the third side
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using the Pythagorean theorem
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The Pythagorean theorem says a squared
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plus b squared equals c squared.
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Where a and b are the legs
and c is the hypotenuse.
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Remember, the hypotenuse
is the longest side
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and it's the side that's
opposite the right angle.
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So, in this case, we are trying to solve
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for c, the hypotenuse.
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So, let's fill in the
numbers that we know.
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You can place the legs wherever you want
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in a and b, but make sure that you have c
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on the other side of the equal sign.
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The hypotenuse over here.
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So, you have 50 squared plus 30 squared
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equals c squared.
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Square 50 and you get 2500.
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You square 30 and you get 900 and
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that's still equal to c squared.
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You add that up, you get
3400 equals c squared.
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But, we're trying to
find c so if it's being
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squared you need to do the opposite
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of that and take the
square root and you're
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gonna do that to both sides to keep your
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equation balanced.
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So, over here, square and square root
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cancel out.
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Over here you take the
square root of 3400.
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Do that on your calculator.
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Put in 3400 and hit the square root key
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and you'll get 58.3.