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Geometry: Circles

200 questions10 skills

Prove that all circles are similar.
Skills for this standard are coming soon.


71 questions3 skills
Identify and describe relationships among inscribed angles, radii, and chords. Include the relationship between central, inscribed, and circumscribed angles; inscribed angles on a diameter are right angles; the radius of a circle is perpendicular to the tangent where the radius intersects the circle.


5 questions1 skill
Construct the inscribed and circumscribed circles of a triangle, and prove properties of angles for a quadrilateral inscribed in a circle.
Construct a tangent line from a point outside a given circle to the circle.
Skills for this standard are coming soon.


124 questions6 skills
Derive using similarity the fact that the length of the arc intercepted by an angle is proportional to the radius, and define the radian measure of the angle as the constant of proportionality; derive the formula for the area of a sector.