Answers Example 17 a x < 11 b x < − 1 7 d a ⩾ − _ 2 c a ⩾ − 9 Answers Exercise 2G 1 a 0 1 2 x 3 U N SA C O M R PL R E EC PA T E G D ES 7 15, 45 8 Andrew $102.50, Brenda $175, Cammi $122.50 9 19 km 10 I am 10years old. 11 first leg = 54 km, second leg = 27 km, third leg = 18 km, fourth leg = 54 km 12 Eric is 18years old now. 13 4 fiction, 8 non-fiction books 14 2 hours 15 8 p.m. 16 rectangle L = 55 m, W = 50 m; triangle side = 70 m 17 a 27, 28, 29 b i x, x + 2, x + 4 ii 4, 6, 8 c i x, x + 2, x + 4 ii 15, 17, 19 d i x, x + 3, x + 6 ii 24, 27, 30 18 a T = 8x + 7200 b 300 c R = 24x d x = 350 e 3825 19 $15 200 20 438 km 21 Anna 6; Henry 4; Chloe 12; twins 11 809 Progress quiz 4 a c 5 a 6 a 7 a 2 x + 7 5xy − x 4a + 28 3a + 4 x = 4 b d b b 1 1 + km a  2b + ab  2 + b − 6x  2 + 15x 5x − 2y 1 b a = 21 c p = − 3_ 2 d t = 20 e x = 11 f k = 7 1 1 c m = − 2 b a = 3 8 a x = 6_ d y = 9_ 3 2 9 a 2(x + 5) = 14 b x − 9 = 4x + 6 10 Let gbe Jed’s team’s goals: g + g + 14 = 30; 22 goals 11 Let abe my age, 4(a + 5) = 88, 17years old 2G Building understanding 1 a 3 > 2 c − 7 < − 3 2 a C b − 1 < 4 d 5 > − 50 c B b A Now you try Example 16 a −1 0 1 2 3 4 −4 −3 −2 −1 0 1 b x c −4 −3 −2 −1 0 1 x 5 2 x 1 2 3 4 x 5 c −3 −2 −1 0 −1 0 1 2 3 0 1 2 3 4 −3 −2 −1 0 1 1 x 2 d x e x f 2 a x < 3 d x ⩾ 3 g m < 6 x 2 3 4 5 6 7 3 a x < 4 b b > 5 e t > − 5 1 h a ⩾ 1_ 2 b n ⩽ − 1 c y > 6 f y ⩾ − 10 i x < 1 d a ⩾ 4 e x ⩾ − 6 g x < − 6 h t ⩽ − 2 4 a x ⩽ 16 b x ⩽ − 9 d x < 11 2 e x > − 2_ 3 b a < − 8 1 e y < − 3_ 5 3 b t > − _ 5 f x ⩾ − 2 cd − b e x < _ a b − cd h x > _ a b − cd f x ⩾ _ 2 c i x < b −  _ a b + 1 k x < _ b−a c − b l x ⩽ _ b−a 3 c x ⩾ _ 5 f x ⩾ 10 5 i m > − 4_ 6 c x ⩽ 20 5 a x < 1 c x ⩽ − 2 4 1 f x < − _ d x < 2_ 7 2 1 3 6 a x ⩾ 2_ c y ⩽ _ 2 8 1 1 e m ⩾ 6 f b < 5_ d a < 1_ 5 2 7 less than 18 8 less than 13 cm 9 a 3 b 2 c 4 d 0 10 x = 3or x = 4or x = 5 11 399 km 12 a i − 0.9, 0, 0.5, 1, 1.8 etc ii Numbers must be less than 2. b i − 4, − 2, 0, 1, 5etc ii Numbers must be greater than − 5. c i x < a ii x > − a 13 a x < 3 b x < 3 c Reverse the inequality sign when dividing by a negative number. 4 14 a x < − 13 b x ⩾ − 3 c x > _ 7 13 10 3 d x ≤ _ e x > _ f x ⩾ _ 5 4 17 b − c b x ⩾ b − a c x ⩽ a(b + c) 15 a x > _ a ac d x ⩽  _ b c g x <  _ a − b b + c j x ⩽ _ 1−a Uncorrected 3rd sample pages • Cambridge University Press © Greenwood, et al 2024 • 978-1-009-48095-6 • Ph 03 8671 1400 2F 1 a 5 + x + y b 4y − 15   2 + p  2 _c k 2 2 d ( m − n) or (n − m) e √x + 16  2 a 1 2 b − 28 d − 12 c _ 1 2 2 3 a 14ab b − 40p  q 4 d − 6y c _ m b