Final: The Curved Track
Part of the Circles section of Coddy's Geometry journey. Lesson 60 of 62.
The curved end of a running track is an arc of a circle with radius 12 meters, centered at O. The runners on that curve cover 10π meters, and the angle the curve turns through at the center is (x + 30)°. Find x.
Challenge
OA and OB are radii of 12 meters, and the arc from A to B is 10π meters long. Tap the central angle, pick the rule that links it to the arc, and solve the board's equation for x.
Then press Check.
Try it yourself
Use the figure to find x
Test yourselfThis lesson includes a short quiz. Start the lesson to answer it and track your progress.
All lessons in Circles
1Parts of a Circle
Center and RadiusChords and DiametersAll Radii Are EqualDiameter Is Two RadiiRecap: Parts of a Circle4Arcs and Sectors
Arc LengthArea of a SectorFind the Central AngleThe Missing Central AngleRecap: Arcs and Sectors2Circumference
Around the CircleUsing the DiameterRadius From CircumferenceCircumference With LettersRecap: Circumference5Radii Make Isosceles
Two Radii, One TriangleBase Angles From the CenterThe Angle at the CenterIsosceles With LettersRecap: Radii and Triangles8Angles on the Same Arc
Same Arc, Same AngleUsing the Same ArcSpot the Bow TieSame Arc With LettersRecap: Same Arc3Area of a Circle
The Area FormulaArea From the DiameterRadius From the AreaCircumference to AreaRecap: Area of a Circle6Inscribed Angles
Meet the Inscribed AngleHalf the Central AngleTwice the Inscribed AngleThe Big ArcInscribed With LettersRecap: Inscribed Angles9Cyclic Quadrilaterals
Four Corners on a CircleOpposite Angles Add to 180Is It Cyclic?Cyclic With LettersRecap: Cyclic Quadrilaterals12Final Challenges
Final: The Pizza SliceFinal: Paths to the PondFinal: The Curved TrackFinal: Deep in the CircleFinal: Angle Into Arc