Circle Theorems Flashcards
1
Q
Alternate segment theorem
A
The angle that lies between a tangent and a chord is equal to the angle subtended by the same chord in the alternate segment.
2
Q
Angle at the centre theorem
A
The angle at the centre is twice the angle at the circumference.
3
Q
Angles in the same segment theorem
A
Angles in the same segment are equal.
4
Q
Angles in a semi circle
A
The angle in a semi circle is 90 degrees.
5
Q
Chord of a circle
A
The perpendicular from the centre of a circle to a chord bisects the chord (splits the chord into two equal parts).
6
Q
Cyclic quadrilateral
A
The opposites angles in a cyclic quadrilateral total 180.
7
Q
Tangent of a circle
A
• The angle between a tangent and a radius is 90.
• Tangents which meet at the same point are equal in length.
