Cogito
Geometry · Chapter 6 · Lesson 3
Tangents and Chords
A tangent meets the radius at a right angle.
11 problems · about 22 minutes · G-C.A.2, G-C.A.4
Figure — use these to answer the problems
Warm Up
Straightforward practice. Get the method working first.
4 problemsRadius 6, tangent 8. Distance to the centre?
AnswerRadius 5, tangent 12. Distance to the centre?
AnswerOne tangent from a point is 9. The other from the same point?
AnswerA radius perpendicular to a chord of 10. Each half is?
Answer
Build It Up
The same ideas with more to keep track of.
3 problemsHow many points does a tangent share with the circle?
AnswerHow many points does a chord share with the circle?
AnswerRadius 8, distance to centre 17. Tangent length?
Answer
Stretch Yourself
Mixed problems. Work out what kind of question it is before you start.
4 problemsChord 24, bisected by a radius. Half the chord?
AnswerMatch each line to how it meets the circle.
Draw a line from each item on the left to its match on the right.
- Tangent
- Chord
- Diameter
- Touches at one point
- Joins two points on the circle
- A chord through the centre
The Right Angle
A tangent meets a radius at what angle, in degrees?
AnswerTo the Centre
Radius 3, tangent 4. Distance from the external point to the centre?
Answer