Fibonacci AFRICA

Fibonacci AFRICA

  • Maths
  • Computers
  • Other
  • About
  • English
  • Italiano
  • Français
  • Deutsch
  • Español
  • English

Theorems as per Grade 11 CAPS document

Click on the link below to open the interactive activity

Proving quadrilateral cyclic

Getting to know the circle

 

If a line is drawn from the centre of a circle perpendicular to a chord, then it bisects the chord.

 

The perpendicular bisector of a chord passes through the centre of the circle.

 

If an arc subtends an angle at the centre of a circle and at any point on the circumference, then the angle at the centre is twice the measure of the angle at the circumference.

 

Angles in the same segment of a circle are equal.

If a quadrilateral is cyclic, then the opposite angles are supplementary.

If two tangents are drawn from the same point outside a circle, then they are equal in length.

The angle between a tangent to a circle and a chord drawn from the point of contact is equal to an angle in the alternate segment.

Summary

© 2019 fibonacci.africa