21.3 Tangents and chords — Practise
Work independently. Questions become more demanding as you progress. Check your answers after you have attempted the set.
- H A tangent touches a circle at . What angle does the radius to make with the tangent?
- H Tangents from touch a circle at and . If cm, find .
- H A perpendicular from the centre meets a chord of length cm. Find each half.
- H The angle between a tangent and chord is . Find the angle in the alternate segment.
- H At a point of contact, the angle between a radius and tangent is . Another angle in the triangle is . Find the third angle.
- H A perpendicular from the centre bisects a chord. One half is cm. Find the full chord length.
- H Two tangents from one point have lengths cm and cm. Find .
- H The alternate segment angle is . The tangent-chord angle is . Find .
- H A perpendicular from the centre bisects a chord. The two pieces are cm and cm. Find .
- H A tangent-chord angle is . The angle at the centre standing on the corresponding arc is twice the angle in the alternate segment. Find the centre angle.
Answers and concise solutions
1. Radius and tangent
Answer:
2. Equal tangents
Answer: cm
3. Bisect the chord
Answer: cm
4. Alternate segment theorem
Answer:
5. Use triangle angles
Answer:
6. Rebuild the chord
Answer: cm
7. Set tangent lengths equal
Answer:
8. Use equal angles
Answer:
9. Equal halves
Answer:
10. Connect two theorems
Answer: