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C. A. B. 1. X. 222º. D. Z. 55º. Session 71 WARM UP. 2. Find m 1. 1. Find m XAB. 42º. 90º. 3. Find m Z. 70º. Two chords intersect INSIDE the circle. Type 1:. a. ab = cd. d. c. b. Example 1:. 9. 12. 6. 3. x. x. 2. 2. X = 3. X = 8. x. 3. 6. 2. X = 1. 12.
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C A B 1 X 222º D Z 55º Session 71 WARM UP 2. Find m1 1. Find mXAB 42º 90º 3. Find mZ 70º
Two chords intersect INSIDE the circle Type 1: a ab = cd d c b
Example 1: 9 12 6 3 x x 2 2 X = 3 X = 8 x 3 6 2 X = 1
12 2x 8 3x Example 2: Find x 2x 3x = 12 8 6x2 = 96 x2 = 16 x = 4
Two secents intersect OUTSIDE the circle Type 2: E A B C D EA * EB = EC * ED
Example 3: B 13 A 7 E 4 C x D 7 (7 + 13) = 4 (4 + x) x = 31 140 = 16 + 4x 124 = 4x
Example 4: B x A 5 D 8 C 6 E 5 (5 + x) = 6 (6 + 8) x = 11.8 25+5x = 84 59 = 5x
Notice that on the tangent segment, the outside is the whole! Secant Segment External Segment Tangent Segment
Type 2 (with a twist): Secant and Tangent C B E A EA2= EB * EC
Example 5: C B x 12 E 24 A (12 + x) 242 = 12 576 = 144 + 12x x = 36
Example 6: 5 B E 15 C x A (5 + 15) x2 = 5 x2 = 100 x = 10
Practice P 220 2-18 even