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Yeah Whoa Okay set match members got a circle here

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and it looks like a non forty five forty five

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ninety trying because you've got thirty five they're OK in

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the circle B is the center of the circle and

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a C'est tangent to the circle If the radius of

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this circle is for what is the area of the

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shaded regions are around you're running short on this place

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Okay so when the lines change into a circle it

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means that it only intersex circle at one measly point

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right there Special thing about tangent lines and circles though

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is that they form right angles with the radius line

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that they intersect Well that lucky angle is a right

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there That's ninety degrees So if we know that and

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we know the thirty five degree angle there then we

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know the fifty five degree angle is right They're right

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We got one eighty minus any money right So well

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to find out what proportion of the circle is shady

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use angle B and compare it to the full three

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sixty degrees The non shaded region is fifty five degrees

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right there so we're just going to subtract that amount

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from the three Sixty to find degrees of the big

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region which is well three Sixteen minus fifty five That's

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three Oh five and there's a bit more calculating to

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Dio We need to find the area and thankfully this

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problem was kind enough to provide the radius So formula

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for the area of a circle is pi r squared

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Right So we got pie four squared or sixteen pie

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And here's the proportion that shows the area of that

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shaded region with access the area So it's three Oh

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five is tow three sixty as axes to sixteen pie

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Well if we multiply it out we get three Oh

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five times that he has sixteen there and that's fifteen

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thousand three hundred thirty one almost dish And that's three

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sixty x They're so Acts here is 42 point six

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The area of the shaded regions The part that looks

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like you know Pac Man eating a lemon wedge is

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forty two point six Yeah they don't give us units 00:01:56.55 --> [endTime] No whatever

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