Show:
Theorems
Vocabulary
Problems
Fill in the blank
Theorems
100

In a circle, if the angle at the center is 80∘, what is the angle at the circumference subtended by the same arc?

The angle at the circumference is half the angle at the center. 

40∘

100

True or False? For every tangent, there is only one point of tangency.

True.

100
AB and CD are both tangent to circle F. AB=5x-28 and CD=3x. Find the measurement of CD.
CD=42
100

Chord AB bisect by OM  the theorem about this stated that 

The _______ bisector of a chord of a circle passes though the center of the circle

perpendicular

100

If a line is perpendicular to a radius of the circle at a point on the circle, then the line is _______ to the circle.

tangent

200

In the same circle, if two angles subtended by the same arc are x and y, what can you say about x and y?

Angles subtended by the same arc in the same segment are equal. 

x=y

200

True or False? A sector is a region bounded by 2 chords and their intercepted arc?

False, A sector is a region bounded by 2 radii not 2 chords.

200
Find the area of the sector if the radius is 6mm and the degree is 120. Round to the nearest hundredth.
37.70 sq. mm.
200

The angle between a tangent and a chord at the point of contact is ______ to the angle subtended by the chord in the alternate segment

equal

200

In a circle, the perpendicular bisector of a chord is a ______ or ________.

radius and diameter

300

If a tangent to a circle at point A and a chord BC intersect at A, what is the relationship between the angle CAB and the angle CBA?

The angle between the tangent and the chord (angle CAB) is equal to the angle in the alternate segment (angle CBA)

angle CAB = angleCBA

300
An angle whose vertex is on a circle and whose sides contain chords on the circle is called?
An inscribed angle.
300
If the measurement of an inscribed angle is 35 degrees, what if the measurement of the intercepted arc?
70 degrees
300

The ________of angles in opposite segments is equal to180 ํ

sum

300

If a quadrilateral is inscribed in a circle, then its opposite angles are _________.

supplementary

400

In a cyclic quadrilateral ABCD, if angle A is 70∘, what measures angle C?

110∘

400
What is the name of the line that intersects a circle at two points?
Secant
400
Find DE and AC. Secants labeled AC and CE, B and D are where the secants meet the circle, respectively. AB=6, BC=4, CD=5, DE=x.
AC=10 and DE=3
400

Angles in the same  __________ are equal

Hint: space on close by arc and chord.

segment

400

If inscribed angles subtend or intercept the same arc, then the angles are _______.

congruent

500

If an angle inscribed in a circle is 50∘, what is the measure of the arc it subtends?

 

The inscribed angle is half the measure of the arc it subtends.

100∘ 

500
A _______ is a line in the same plane as the circle that intersects it at exactly one point. (FILL IN THE BLANK)
Tangent
500
Write the equation of the circle. Circle G with center (9,-2) and radius 4.
(x-9)^2 + (y+2)^2 = 16
500

An angle at the center of a circle is twice that of any angle at the circumference _______ by the same arc,

subtended

500

An inscribed angle subtends a(n) ________ if and only if the angle is a right angle.

semi-circle