Watch the following videos to learn about all of the parts of a circle that we need to know! It's a lot of information! Watch the first video, and if you still have quesitons, watch the second one! Please don't skip... you're brain needs it!
If you need more help, watch the second video.
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Now it's time to take some notes. In your notebook, you should label a section called Circumference and Area of Circles. Please write today's date as well. In your notes, you should write down the definititions of:
Radius -
Diameter -
Circumference -
Pi -
Remember to leave enough room for a definition and picture! Complete the following lesson to get your definitions.
Radius, diameter, & circumference
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In your notes, write down the two equations you can use to solve for the Circumference. Then write one of those equations below.
Watch the following video if you need help solving for the circumference, radius, or diameter of a circle. If you think you understand the circumference equation, move and and complete the lessons.
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Here's a couple quick little lessons to make sure our knowledge of circles is sizzling
Radius and Diameter
Circumference of a Circle
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Find the perimeter of the polygon.
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What is the diameter of the orange above?
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What is the circumference of the delicious looking basil pizza above? Leave your answers in terms of pi.
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Find the perimeter of the window. Leave your answers in terms of pi.
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What is the circumference of the light blue circle in the image above? Leave your answer in terms of pi.
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A wire is bent into four perfect semi-circles. What is the length of the wire, in cm? Leave your answer in terms of pi.
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As best you can, draw and label a circle with the following circumference:
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“Lines” of latitude on Earth are actually circles. The Tropic of Cancer is the northernmost line of latitude at which the Sun appears directly overhead at noon. The Tropic of Cancer has a radius of 5854 kilometers.
To qualify for an around-the-world speed record, a pilot must cover a distance no less than the circumference of the Tropic of Cancer, cross all meridians, and land on the same airfield where she started.
Write an equation to solve for the minimum distance that a pilot must fly to qualify for an around-the-world speed record? Use parantheses to denote multiplication.
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For the question above, solve the equation you created to find the minimum distance that a pilot must fly to qualify for an around-the-world speed record? Your answer should be in terms of pi.
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Estimate the perimeter of the arrow.
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Find the perimeter of the figure.
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Describe and correct the error in finding the perimeter of the figure.
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Explain how you could find the perimeter of this shape. Round your answer to the nearest whole foot.
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The figure is made up of a square and two semicircles. Find the perimeter. Leave your answer in terms of pi.
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You run around the perimeter of the baseball field at a rate of 9 feet per second. How long does it take you to run around the baseball field? Round your answer to the nearest second.
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How can you add a figure to a composite figure without increasing its perimeter? Draw the before and after diagrams to support your answer.
