circle theorems.

Question 1

define circle theorems.

Answer 1

laws that apply to both angles and lengths when circles are involved.

Question 2

what are the 7 main circle theorems?

Answer 2

• alternate segment theorem.
• angle at the centre is twice the angle at the circumfrance.
• \ngles in the same segment are equal.
• angle in a semi circle.
• chord of a circle.
• tangent of a circle.
• cyclic quadrilateral.

Question 3

what is the alternate segment theorem?

Answer 3

the angle that lies between a tangent and a chord is equal to the angle subtended by the same chord in the alternate segment.

Question 4

what is the rule for angle at the centre theorem?

Answer 4

the angle at the centre is twice the angle at the circumfrance.

Question 5

what is the angles in the same segment theorem?

Answer 5

angles in the same segment are equal.

Question 6

what is the rule for angles in a semi-circle?

Answer 6

the angle in a semicircle is 90 degrees.

Question 7

what is the rule for chord of a circle?

Answer 7

the perpendicular from the centre of a circle to a chord bisects the chord.

Question 8

what is the rule for cyclic quadrilateral?

Answer 8

the opposite angles in a cyclic quadrilateral total 180 degrees.

Question 9

what is the rule for tangent of a circle?

Answer 9

• the angle between a tangent and a radius is 90 degrees.
• tangents which meet at the same point are equal in length.