Circles Vocabulary
The distance from the center of a circle to any point on the circle
Radius
The space around the circle
Circumference
An angle whose vertex is located at the center of a circle
Central angle
An angle whose vertex lies on the circle and whose sides are chords
Inscribed angle
If an angle is formed on the inside of a circle, to find the measure of the angle, what operation do we perform
Addition
A shape with four sides and four right angles
Rectangle
A line segment that connects two points on a circle but does not have to pass through the center
Chord
The space that covers the inside of the circle
Area
The sides of a central angle are called
Radii or 2 radius
If an inscribed angle intercepts an arc measuring 80 degrees, the angle measure is
40 degrees
If an angle is formed on the outside of a circle, to find the measure of the angle, what operation do we perform
Subtraction
The number that appears the most in a data set
Mode
A line that touches a circle at exactly one point
Tangent
A straight line has a measure of
180 degrees
The measure of a central angle is equal to the measure of its intercepted
Arc
All inscribed angles that intercept the same arc have this relationship
They are congruent
A secant intersects a circle at how many points
Two points
The force that pulls gravity towards Earth
Gravity
A line that intersects a circle at two different points
Secant
A circle measures how many degrees
360 degrees
If a central angle measures 65 degrees, the measure of the arc is
65 degrees
An inscribed angle that intercepts a semicircle always measures this
90 degrees
Whether angles are formed inside, outside, or on the circle, what do we always do to find the measure of the angle
Divide by 2
The imaginary line that divides Earth into the Northern and Southern Hemispheres
Equator
A chord that passes through the center of the circle
Diameter
A piece of the circumference of a circle is called
Arc Length
A circle is divided into 6 congruent sections by central angles. Each central angle measures this many degrees
60 degrees
If an inscribed angle measures 35°, the intercepted arc must measure this
70 degrees
Angles formed inside the circle can be formed using
Chords and secants
What fraction represents one out of four equal parts?
1/4
Part of a circle formed between two points on the circle and measured in degrees
Arc
A "piece of the pie" of a circle is called
Area of the Sector
Two central angles intercept arcs of equal measure. The angles must have this relationship
They are congruent
Two different inscribed angles intercept a 100° arc. Each angle measure is this
50 degrees
Angles formed outside the circle can be formed using
Tangents and secants
What do we call an angle smaller than 90 degrees
Acute angle