Circle Theorems
1. **Problem Statement:**
You are designing a circular park and need to apply theorems involving chords, arcs, secants, and tangents.
2. **Chord Theorem:**
- Identify a chord, say chord AB.
- Draw its perpendicular bisector, which is a line that cuts AB into two equal parts at a right angle.
- This bisector passes through the center of the circle because the perpendicular bisector of any chord in a circle always passes through the center.
3. **Intersecting Chords Theorem:**
- The intersecting chords are AB and CD, intersecting at point E inside the circle.
- Given AE = 4 cm and EB = 6 cm, the product AE × EB = $4 \times 6 = 24$ cm².
- If CE = 3 cm, then by the theorem, AE × EB = CE × ED, so $24 = 3 \times ED$.
- Solving for ED gives $ED = \frac{24}{3} = 8$ cm.
4. **Tangent–Chord Angle Theorem:**
- The tangent touches the circle at point P.
- Draw a chord from P to another point on the circle, say point A.
- The angle between the tangent at P and chord PA equals the angle subtended by chord PA in the alternate segment of the circle.
**Final answers:**
- The perpendicular bisector of chord AB passes through the center.
- $AE \times EB = 24$ cm².
- $ED = 8$ cm.
- The tangent–chord angle theorem relates the angle between tangent and chord to the angle in the alternate segment.