# Math Unit 5: Circles Lesson 1

## Unlock all answers in this set

question
arc of a circle
a part of a circle between two given endpoints
question
central angle
an angle whose vertex is at the center of a circle and whose sides are radii of that circle
question
chord
a segment with both endpoints on a circle
question
circle
the set of all points in a plane that are equidistant from a given point
question
concentric circles
circles that lie in the same plane and have the same center
question
diameter
a chord that passes through the center of the circle
question
major arc
an arc whose measure is greater than or equal to 180 degrees
question
minor arc
an arc whose measure is less than 180 degrees
question
point of tangency
the point of intersection between a circle and its tangent
question
a segment that extends from the center of a circle to any point on the circle
question
secant
a line or ray that intersects a circle at exactly two points
question
semicircle
an arc whose central angle has sides that intercept the circle at opposite endpoints of a diameter
question
similarity transformation
a composition of rigid, or isometric, transformations with one or more dilations
question
tangent to a circle
a line, line segment, or ray that intersects a circle at exactly one point and contains no points inside the circle
question
Warm-up Use the diagram to complete the statements. This is circle BLANK (1) If the distance from A to C is 6 units, then the distance from C to B is BLANK (2) units. https://media.edgenuity.com/contentengine/frames/5f818e1a-c2be-11e4-9204-bc764e05bde9/8101-09-01-05-03-image1.png
1. C 2. 6
question
Lesson (skipped slide 3 & 7) Which statement is true? https://media.edgenuity.com/contentengine/frames/83c0ab94-c2be-11e4-9204-bc764e05bde9/8101-09-01-10-05-image1.png
SR is a secant of circle P.
question
Which circle with center U shows a central angle whose intercepted arc, ZV , measures 58°?
B (Z V with 58°) https://media.edgenuity.com/EVresources/8101/8101-09/8101-09-01/8101-09-01-10/8101-09-01-10-10/8101-09-01-10-10-image2.png
question
Which statements are correct? Check all that apply. https://media.edgenuity.com/contentengine/frames/b76a464e-c2be-11e4-a0d6-bc764e05bde9/8101-09-01-10-12-image1.png
- One major arc is GHE - Arc FE is a minor arc. - The measure of FE is 41°.
question
In circle P, the measure of ∠QPS is 15° and RQ is a diameter. Find the arc measures. 1. mQT= 2. mRT= 3. mQTR= https://media.edgenuity.com/contentengine/frames/c6f5f018-c2be-11e4-b7e4-bc764e05bde9/8101-09-01-10-14-image1.png
1. 120 2. 60 3. 180
question
Assignment Which circle C shows a chord that is not a diameter?
D https://media.edgenuity.com/EVresources/8101/8101-09/8101-09-01/8101-09-01-20/8101-09-01-20-01/8101-09-01-20-01-image4.png
question
Identify the parts relating to A. 1. What is FG 2. What is DB 3. What is DH 4. What is AC https://media.edgenuity.com/contentengine/frames/eb85c35e-c2be-11e4-b7e4-bc764e05bde9/8101-09-01-20-02-image1.png
1. Secant 2. Tangent 3. Secant 4. Radius
question
Circle A has a radius of 6. Which circles are congruent to circle A? Check all that apply. https://media.edgenuity.com/contentengine/frames/f303784c-c2be-11e4-8e27-bc764e05bde9/8101-09-01-20-03-image1.png
- circle E - circle F
question
Complete the statements about circle Z. A central angle, such as angle BLANK (1) of circle Z, is an angle whose vertex is BLANK (2) and whose sides are radii of the circle. Angle BLANK (3) is not a central angle of circle Z. The degree measure of an arc is BLANK (4) he degree measure of the central angle that intercepts it. The measure of TU is BLANK (5) degrees. https://media.edgenuity.com/contentengine/frames/fa866732-c2be-11e4-b8b9-bc764e05bde9/8101-09-01-20-04-image1.png
1. UZV 2. the center of the circle 3. WSX 4. equal to 5. 79
question
Which statements are correct? Check all that apply.
- A diameter is always a chord. - A tangent is never a secant. - A chord can be shorter than a radius of the same circle. - A radius is always congruent to another radius of the same circle.
question
NL and MK are diameters of circle J. Complete the statements about circle J. MP is a BLANK (1) and measures BLANK (2) degrees. MLN is a BLANK (3) and measures BLANK (4) degrees. https://media.edgenuity.com/contentengine/frames/0bde1e44-c2bf-11e4-a0d6-bc764e05bde9/8101-09-01-20-06-image1.png
1. minor arc 2. 152 3. major arc 4. 298
question
GD is a diameter of circle C. What is mGEB? https://media.edgenuity.com/contentengine/frames/127f23ce-c2bf-11e4-879b-bc764e05bde9/8101-09-01-20-07-image1.png
231°
question
How is a tangent different from a chord? Explain.
Sample Response: A tangent intersects a circle at only one point, while a chord intersects the circle at two points. Also, a chord is contained within a circle, but a tangent is outside the circle, except for the point of tangency, which lies on the circle.
question
EH is a diameter of D. The measure of is (10x + 8)° and the measure of GH is (11x)°. Determine the values. 1. The value of x is . 2. The measure of EF is degrees. 3. The measure of GH is degrees. https://media.edgenuity.com/contentengine/frames/25977e7a-c2bf-11e4-8e27-bc764e05bde9/8101-09-01-20-09-image1.png
1. 5 2. 58 3. 55
question
Concentric circles with center G have radii 5 and 11 as shown. Which would prove that the circles are similar? Dilate the smaller circle by a factor of BLANK (1) If the circles were not concentric, what additional step would be needed to prove they are similar? BLANK (2) one of the circles so that the circles have the same center. https://media.edgenuity.com/contentengine/frames/2e6f6fe4-c2bf-11e4-b8b9-bc764e05bde9/8101-09-01-20-10-image1.png
1. 11/5 2. translate
question
Quiz Circle X with a radius of 6 units and circle Y with a radius of 2 units are shown. Which steps would prove the circles similar? https://media.edgenuity.com/evresources/8101/8101-09/8101-09-01/8101-09-01-assessment/8101-09-01-27.PNG
Translate the circles so they share a common center point, and dilate circle Y by a scale factor of 3.
question
In circle O, AE and FC are diameters. Arc ED measures 17°. What is the measure of EFC? https://media.edgenuity.com/evresources/8101/8101-09/8101-09-01/8101-09-01-assessment/8101-09-01-17.png
253°
question
What does CDE describe? https://media.edgenuity.com/evresources/8101/8101-09/8101-09-01/8101-09-01-assessment/8101-09-01-03.png
a major arc
question
Which is true regarding chords and diameters of circles?
Both chords and diameters have two endpoints on a circle. Diameters must intersect the center of a circle.
question
In circle D, which is a secant? https://media.edgenuity.com/evresources/8101/8101-09/8101-09-01/8101-09-01-assessment/8101-09-01-01.png
GH
question
In circle O, SU is a diameter. What is mST? https://media.edgenuity.com/evresources/8101/8101-09/8101-09-01/8101-09-01-assessment/8101-09-01-26.png
130°
question
How are the semicircle and the diameter of a circle related?