Maths Worksheet - Geometry (answers)

SAEP Matric Success – Zisukhanyo Maths Worksheet Tuesday 21st April 2009 Geometry – ANSWERS 1. Study & Master, HG, Test 19A, Q1, 2 & 4 a) a = 40° b) b = 64°, c = 42°

c) f = 25°, g = 28°

2. Study & Master, HG, Test 19B, Q1, 2 & 3 a) a = 75°, b = 105° b) c = 100°, d = 45°

c) e = 36°, f = 60°

3. Study & Master, HG, Test 19C, Q2, 3 & 5 a) b = 65°, c = 55° b) d = 65°, e = 65°, f = 130° c) j = 40°, k = 50°, l = 90° 4. Study & Master, HG, Test 19D, Q2.1 36,7 cm 5. Study & Master, HG, Test 19D, Q4 a) 90 – x b) Show that angle CBT is also 90 – x to prove this c) AC = ((√15)/2)r 6. Study & Master, HG, Test 19D, Q5 a) O1=O2 (=90°). BO is common to triangles BOC and BOD. CO = DO. Therefore triangles BOC and BOD are identical (i.e. congruent). Therefore B1 = B2. b) angle CED = angle CBD = 2 x B1. c) angle CPA = 2 x B1 = angle CED. Therefore CEFP is a cyclic quad because an exterior angle is equal to the opposite interior angle. 7. Study & Master, HG, Test 18, Q1 a) 2 b) 2y = -x + 29

c) y = x – 5

d) 8,2°

8. Study & Master, HG, Test 18, Q15 Centre: (3 ; -1). Radiu = √2. Distance = √8 = 2,83. 9. Study & Master, HG, Test 18, Q16 a) (x – 5)2 + (y – 4)2 = 25 c) AP is y = -0,75x + 1,5. BP is 0,75x – 6 e) Centre (5 ; 7/8) (midpoint of MP)

b) A(2 ; 0) and B(8 ; 0) d) P(5 ; -2,25) f) 73,8°