Circle Geometry and Theorems By Jonathan and Aislinn Circle Geometry and Theorems

Task A - diameter Circle diameter.

Task a - chord Circle chord.

TASK A - tangent Circle tangent

Task A This is an isosceles triangle. Because two of the sides are the same and the third one is not.

Task B – angles subtended from the diameter We noticed that angle D is 90 degrees.

TASK B – ANGLES IN THE SAME SEGMENT Circle theorem of chords Angles subtended from the same segment of a chord are always the same. “ Given a chord all angles from that chord are equal”

Task b – angles subtended at the centre “For any chord the angle subtended at the centre is twice that subtended at the perimeter.”

Task b – angles in a cyclic quadrilateral “Opposite angles of a cyclic quadrilateral add up to 180 degrees”

Task b – angles between tangent and radius The angle is 90 degrees when the line touches the circle at certain point.