Circle Theorems Flashcards
(8 cards)
1 semi circle
The angle in a semi-circle is always 90 degrees
2 circumference and centre
The angle at the circumference is half the angle at the centre
3 - angles in the same segment?
The angles in the SAME SEGMENT from a COMMON CHORD are equal
4 - quadrilateral?
The opposite angles in a cyclic quadrilateral always add up to 180 degrees
5 - tangent ?
The angle between a radius and a tangent is 90 degrees
6 - Alternate Segment Theorem
The angle between the chord and the tangent is equal to the opposite angle inside the triangle
7 - The tangents equal?
The tangents to a circle from the SAME POINT will be equal length
8 - chord ?
The radius through the midpoint of a chord will bisect the chord at 90 degrees