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Geometry: Circles

159 questions8 skills

HSG-C.A.1

14 questions1 skill
Prove that all circles are similar.
Similarity & transformations

HSG-C.A.2

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.
Inscribed angles
Tangents of circles problems
Inscribed shapes

HSG-C.A.3

Construct the inscribed and circumscribed circles of a triangle, and prove properties of angles for a quadrilateral inscribed in a circle.
Skills for this standard are coming soon.

HSG-C.A.4

Construct a tangent line from a point outside a given circle to the circle.
Skills for this standard are coming soon.

HSG-C.B.5

74 questions4 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.
Radians & degrees
Arc measure with equations
Arc measure
Radians & arc length