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(b) 2x 2 (c) PQ = 3 (3) cm
13 1 4
(x 3 ) 2 = 2.25 cm [1]
= 2x 13 2 8 (a) Volume
x 6 = (x + 6)(2x)(2x – 1)
–
= 2x 6 1 [3] = (2x + 12x)(2x – 1)
2
3
(c) 2 × 2 = 2 = 4x + 22x – 12x cm 3 [2]
–
–2a
2
3
7
2
( )
–2a + – 3 = 7 (b) (i) Length = 2x – 4 cm
Width = 2x – 1 – 4

2
−2a = 17 = 2x – 5 cm
2 Height = x + 6 – 2
(ii) (x – 9)(3x + 32) = 0Reserved.
a = − 17 [3] = x + 4 cm [3]
4 (ii) Volume = (2x – 4)(2x – 5)(x + 4)
6 (a) 2x – 25y = 135 = (4x – 18x + 20)(x + 4)
2
2
y = 4x – 2x – 52x + 80 [2]
3
2x = 9 – 5 (c) (i) (4x + 22x – 12x) – (4x – 2x – 52x + 80)
3
2
2
3
y = 2224
9 – = 135 + 25y
5 24x + 40x – 80 – 2224 = 0
2
45 – y = 675 + 125y 3x + 5x – 288 = 0 (shown) [2]
2
Penerbitan Pelangi Sdn Bhd. All Rights
126y = –630
y = –5 x = 9 or x = – 32 (invalid)
2x = 9 – (–5) 3
x = 5 5 [4] Length = 2(9) = 18 cm
(b) y = 3 – x Width = 2(9) – 1 = 17 cm
x + 3x = 3 – x + 2 Height = 9 + 6 = 15 cm
2
x + 4x – 5 = 0 2x cm is the longest side. [3]
2
(x + 5)(x – 1) = 0 9 (a) 50 kg [1]
x = –5 or x = 1 x
y = 8 or y = 2 [4] (b) 50 – 50 = 1.25
x x + 2
(c) y = 21 – x – 4 50(x + 2) – 50x
7 x(x + 2) = 1.25
y = 17 – x 1.25x + 2.5x – 100 = 0
2
7 x + 2x – 80 = 0 (shown) [3]
2
y + 4 = 9 + 3 – 6x (c) x + 2x – 80 = 0
2
5 (x – 8)(x + 10) = 0
y = 5 + 3 – 6x x = 8 or x = –10 [2]
5
28 – 6x (d) Increased price = $8 + $2
y =
5 = $10 [1]
17 – x 28 – 6x 10 (a) Kaylee’s age on April 2018 = x – 2
=
7 5 Lily’s age on April 2018 = 4(x – 2)
85 – 5x = 196 – 42x = 4x – 8 [2]
37x = 111 (b) (x + 2)(4x – 6) = 9(x – 2) 2
2
2
x = 3 9x – 4x – 36x – 2x + 36 + 12 = 0
2
y = 17 – 3 5x – 38x + 48 = 0 (shown) [2]
7 (c) (x – 6)(5x – 8) = 0
y = 2 [4] x = 6 or x = 8
( ) 5
3y
(y – 3 + y) Lily’s age on April 2018 = 4(6) – 8 = 16
7 (a) Area = 4 Lily’s age on April 2010 = 16 – 8 = 8 [2]
2
6y – 9y
2
= [2] Functions
8
(b) 6y – 9y = 27 ( 3 ) 2
2
2y – 3y − 9 = 0 1 (a) hg(x) = x + 1 – 2
2
(y – 3)(2y + 3) = 0 9 6
3 = 2 + – 1
y = 3 or y = – [2] x x
2
Cambridge IGCSE
TM
160 Ace Your Mathematics
Answers.indd 160 15/03/2022 11:08 AM