← 2.4 Circles, Chords and Tangents
A tangent meets the radius
Mathematics · Grade 11 · about 40 minutes
A tangent is perpendicular to the radius at the point of contact, so the tangent length comes from Pythagoras.
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Other lessons in this sub-strand
- The line from the centre to a chord
- Two chords that cross
- A tangent meets the radius
- The two tangents from one point
- Drawing the tangents
- A tangent and a secant
- Two secants from one point
- The alternate segment
- A direct common tangent
- A transverse common tangent
- When two circles touch
- The circle through three vertices
- The incircle and an excircle
- Centroid and orthocentre