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Tangent Properties: Radius Perpendicularity and External Tangents

Circle Theorems: Angles, Chords, and Tangents

10th Grade·Math·Open Global Math

Updated 1 month ago · 5 views

Prove that a tangent line is perpendicular to the radius at the point of tangency and tangent segments from a common external point are congruent.

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Circle Theorems: Angles, Chords, and Tangents

10th Grade · Math · Open Global Math

6 lessons

Goal

Prove and apply theorems concerning central, inscribed, and circumscribed angles, tangent lines, and intersecting chords.

6 lessons

0 of 6 done

Similarity of All Circles and Arc Length RelationshipsUp next
Inscribed Angle Theorem and CorollariesNot started yet
Angles Formed by Tangents, Secants, and ChordsNot started yet
Tangent Properties: Radius Perpendicularity and External TangentsYou are here
Chord Theorems: Perpendicular Bisectors and Congruent ChordsNot started yet
Intersecting Chords, Secants, and Tangents Segment LengthsNot started yet

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Learning standards covered

OGM.11.GEO.5Open Global Math Standards 2026™ · 10th Grade

Prove and apply theorems concerning circles (similarity of circles, relationships among central, inscribed, circumscribed angles, radii, chords, secants, tangents, and inscribed quadrilaterals); construct inscribed and circumscribed circles of triangles.