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Warm – up Session 48. EOCT Review. Question of the Day. Homework Review. CCGPS Geometry Day 48 (3-28-14). UNIT QUESTION: What special properties are found with the parts of a circle? Standard: MMC9-12.G.C.1-5,G.GMD.1-3 Today’s Question:
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EOCT Review Question of the Day
CCGPS GeometryDay 48 (3-28-14) UNIT QUESTION: What special properties are found with the parts of a circle? Standard: MMC9-12.G.C.1-5,G.GMD.1-3 Today’s Question: What other angle relationships do we know for circles? Standard: MMC9-12.G.C.2
Two circles can intersect… • in two points • one point • or no points
No points of intersection (same center) Concentric Circles Same center but different radii
1 point of intersection(Tangent Circles) Externally Tangent Internally Tangent
More Pythagorean Theorem type problems! Yeah!! Point of Tangency If a line (segment or ray) is tangent to a circle, then it is perpendicular to the radius drawn to the point of tangency.
1. Find x A 12 B 9 a2 + b2 = c2 x 92 + 122 = x2 x = 15
2. Find RQ a2 + b2 = c2 122 + (QR)2 = (8+12)2 P 122 + (QR)2 = 202 12 8 RQ = 16 R Q
3. Is BC tangent to the circle? a2 + b2 = c2 ? No A 32 C 16 24 B
r2 + 242 = (r + 16)2 4. Find the radius. r2 + 576= r2 + 32r + 256 320= 32r 16 r = 10 A C 24 B
A green on a golf course is in the shape of a circle. Your golf ball is 8 feet from the edge of the green and 32 feet from a point of tangency on the green. • What is the radius? • b) How far is your ball from the cup at the center? x = 60 ft. x = 68 ft.
S Party hat problems! If two segments from the same exterior point are tangent to a circle, then they are congruent. R T
6. Find x R S T
7. Find x R S T
8. Find x C A B
9. Find x. B A C P D E
10. Find NP N T S P R Q
CW Workbook Page 199 #18-33
HW Worksheet