Tangent length
Power Mechanics · Grade 10 · about 40 minutes
Because the radius meets the tangent at 90 degrees, the length of a tangent from an outside point is just Pythagoras.
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- 9 sections of explanation, worked examples and diagrams
- 1 practice task with hints and worked answers
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Other lessons in this sub-strand
- What a tangent is
- A tangent at a point on the circle
- A tangent from a point outside the circle
- Why the semicircle method works
- Tangents parallel and square to a line
- External tangents to two equal circles
- External tangents to two unequal circles
- Internal tangents to two equal circles
- Internal tangents to two unequal circles
- Tangent length
- Checking a tangent construction
- Tangency in belt and chain drives
- Tangency in gears, cams and wheels
- Why tangency matters in drawing