180 likes | 286 Views
Welcome to A d ay F ull of Arcs!. You will need on your desk the following: pencil pen ruler protractor compass calculator whiteboard pen Write Hw #3 in Homework Assignment List HW#3 Pg. 760 #1-14 (1 st period: worksheet from yesterday) Due: 3/13.
E N D
Welcome to A dayFull of Arcs! You will need on your desk the following: • pencil • pen • ruler • protractor • compass • calculator • whiteboard pen Write Hw #3 in Homework Assignment List HW#3 Pg. 760 #1-14 (1st period: worksheet from yesterday) Due: 3/13
Welcome to A day Full of Arcs! Please take out your homework • Tonight’s HW: • P 755: “Try This” problems ( #1-3) • P760: #1-4, 11-14, 33 ,34
Announcements Thursday • CAHSEE Practice Friday • PI DAY!!!! • Bring in a circular object (if you want, it can be food!)
Trig Test Please step outside if you are the following: Please only have a red pen on your desk.
Going over your test I am going to give you 5 minutes to look over your test and ask your neighbors any questions that you may have.
Trig Test A: 35-39 B: 31.5-34.5 C: 27.5- 31 Below a 27- please come see me!
Averages Period 1 85% Period 3 75% Period 4: 77%
Learning Objective(s) By the end of the period you will be able to: • Find the central angle and arc measures in a circle.
Central Angles • Central angle • An angle whose vertex is the center of a circle What do you think central angles add up to? 360 degrees!
11-2 Arcs and Chords Arc • The piece of the circumference between two points on a circle called the endpoints. • We use a rainbow over two letters to identify an arc. AB Today we are discussing arc measures. Therefore, the arc is a degree. We will discuss arc length later; this is a distance.
11-2 Arcs and Chords Minor Arc • An arc whose points are on or in the interior of a central angle. • The measure of a major arc is: mAC = m∠ABC • Smaller than 180 degrees. • Only need two letters to name the arc. • Notice: ∠ABC is the central angle!
11-2 Arcs and Chords Major Arc • An arc whose points are on or in the exterior of a central angle. • The measure of a major arc is: mADC = 360° - m∠ABC • Larger than 180 degrees. • Must use three letters to name (this is what distinguishes a major and minor arc). How do you predict we can find the measure of a major arc?
Semicircle Semicircle • The endpoints of an arc lie on the diameter. • The measure of a semicircle is 180°. mEFG= 180° • Must use three letters to name. What do you predict is the measure of a semicircle arc?
Review! Which topic do you all what to review? • Identifying parts of a circle. • Circles and Transformations. • Circles and Arcs.