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10-2 Measuring Angles and Arcs day 2. You measured angles and identified congruent angles. Identify central angles, major arcs, minor arcs, and semicircles, and find their measures. Find arc lengths. Arc-Additional Theorem.
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10-2 Measuring Angles and Arcs day 2 You measured angles and identified congruent angles. Identify central angles, major arcs, minor arcs, and semicircles, and find their measures. • Find arc lengths.
Arc-Additional Theorem The measure of two adjacent, nonoverlapping arcs is the sum of the measures of the two arcs. That is if C is on arc AB, then mAB = mAC + mCB A C B p. 708
Find each arc measure. • mRST • mDE • mHGF S 320° 120° 191° T 40° R D 60° E H 153° G 38° F
Answer: . Arc Addition Postulate = 58 + 32 Substitution
Answer: Arc Addition Postulate = mIMJ + mJMK Substitution = 90 + 58 = 148
A. 180 B. 90 C. 52 D. 38
A. 52 B. 90 C. 142 D. 180
Arc Lengths B Arc lengths are the pieces of the circumference cut by central angles. Arc lengths are measured in units of measure like inches and centimeters. Can arc length be measured with a ruler? A Arc length
L 125° 12 cm J K is a central angle of סּK Find the arc length (L) of JL to the nearest tenth. C = 2 π r (circumference) The arc covers 125° out of a total of 360° or
A 30° C If the circumference of a circle is 21π, what is the length of a 30° arc? B
cm Use a calculator. Answer: Arc Length Equation Substitution
Answer: Arc Length Equation Substitution Use a calculator.
Answer: Arc Length Equation Substitution Use a calculator.
A. 3.56 cm B. 3.77 cm C. 3.98 cm D. 4.21 cm
A. 36.56 cm B. 37.79 cm C. 38.61 cm D. 40.21 cm
A. 32.99 cm B. 33.59 cm C. 33.89 cm D. 34.61 cm
What is an arc length? Arc lengths are the pieces of the circumference cut by central angles. • How do you find arc length?
10-2Assignment Day 2 Page 711, 27-41 odd