Maths HT 1 test

How to figure out an interior angle based on number of sides

(no. of sides - 2)*180/no. of sides

How to figure out an exterior angle based on interior angle

180 - Interior angle = exterior angle

Angle at the center and circumference

The angle at the center is always twice of that at the edge of the circumfrence

“Bow tie rule“

Angles in the same segment are equal

quadrilateral + circle

Opposite angles in a cyclic quadrilateral add to 180*

Exterior of cyclic quaderilateral

An exterior angle in a cyclic quadrilateral will always be equal to the opposite interior angle.

What is a chord?

a line joining two points on the edge of a circle

What does a chord do

Splits the circle into a minor and a major segment

Perpendicular bisector of a chord

The perpendicular bisector of a chord is the line that cuts it in half at a right angle - it always goes through the curve of the circle

What is a tangent?

A tangent is a line touching the circle at one point only

Angle of a tangent at the point of contact?

A tangent is perpendicular to the circle at the point of contact.

Drawn from the same point length

Two different tangents drawn from the same point are equal in length

BIG ONE TO LEARN

The angle between a tangent and a chord is equal to the angles in the alternate segment