Central angel

The angle in a circle whose vertex is the center of the circle is called the

CENTRAL ANGLE

Inscribed angle

• Inscribed angle is defined as the angle formed by 2 chords that meet at the same point on a circle

chord

• A straight line connecting 2 points on a curve.

Area of a circle

• (pie r2) where r=the radius of the circle of pie =3.141592 a=pi r 2

circumference

• The circumference of a circle is the perimeter—the distance around the outer edge.

radius

• The radius of a circle is the distance from the center of the circle to the outside edge.

diameter

• The diameter of a circle is longest distance across a circle. (the diameter cuts through the center of the circle. this is what makes it the longest distance.)

sector

• The area between an arc and two radii of a circle. Also referred as wedge. The region enclosed to two and an arc. The two radii divide the circle into 2 sectors called a major sector and a minor sector.

Standard form

• (x-h) 2+(y-k) 2.the center is at (n,k). The radius is r

Transformation form

• (x-h\r)2 +(y-k\r)2=1

General form

• ax2+by2+cx+1y+e=0

Mapping notation

• (x,y)-------------(rx+h,ry+k)• Center (h,k),radius =r