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English Pages [47] Year 2021
ANSWERS
Unit 1 Answers
4 a 2 6
E1.1
e 215
b 3 6
1 a x 6
b 28
c 8x 6
2 a 3 5 1 3 a 4
b 4 1 b 36
c 6 5 1 c 8
3 e 2
f
( 1 + m1 ) = a( mmn+ n )
b 3x
c
e 1
−1 f x 6
−1 g x 4
−1 3 a x 2
1 b x 3
−1 c x 4
4 a x = 8
b y = 100
1
1 2x 2
b 81
e 25
f 49
4
3 a x 3
12
g 4 2
h 5 5
10 h 3
3 a x = 3
b y = 3 3
c z = 3
1 125 125 e 216 2 a 5 e 81
3
b x 4 13
b x 3
1 a 5 32 5 3
d 3
h 3x
1 e 6 7 7
3 2
j 7
b 32
c 1000
e 8
f 1000
1 1 0.2 5 2 32 = (32) 5 = (2 ) 5 = 2
3 a 2.4
c 125 3
c x 2
5 a 3
d 16
b 1
c 4.6
5
d x 2
7
c x 6
1 8 8 f 27 b
b 2 f 3
c
64 27
d 32 = 9
d 256
c 2401
d 4
7
−
5
1 a 2 2
b 2 3
c 2 2
d 2 3
8 2 a 715
3 b 3 2
1 c 2 4
1 d 2 4
1 1 3 a 2 2 × 3 2 1 1 e 2 4 × 52
1 1 b 2 3 × 7 3 1 1 2 2 × 33
1 c 3 × 2 4
1 1 d 2 2 × 5 2
f
b 3
2 a 7x3
b
3 a 1000
b 100
c
1 9
d
1 27
4 a 4
b
27 8
c
25 16
d
25 27
f 2 1 4x
d 3
5
5 a 2 2
b 3 4
6 a 25
b
7
c 2
7
d 2 3 × 3 3
1 2
c 7
7 a 27
b 2 6
c 2
d 3 3
e 2
f 8
1 g 12 12
1 h 12 3
3
c 9 d 2
1 c 5 5 g 2 3 c 2x
1 1 a 3 3 e 4
5
Practice 4 7
b 2
Mixed practice
f 16
3 Student’s own answers 1 4 a b 4 9
7
i
9 2
Practice 6
10 d 2 x
Practice 3 1 a
j
6 3 6 b 12 37 × 2 c 24 × 37 d 25
f 55
4
e x 15
i 26 5
3
4
h 10 37
4 x = 1024
1 a 4 2
e 7
g 15 25
d 5
Practice 2
2 a x 3
6
1 d 6 11
6
2 a 25
2 a 2 x 2
c 6 5
b 3
1 a 2
Practice 1 1 f 3
( 1 − m1 ) = a( mmn− n )
h a n
Practice 5 d 2
f 35
1 c 2 5 g 2
d 2 6 3 6
f 2 n
g a n
25 4
b 2
1 1
3
c 710
( 1 _ m1 ) × 5 ( 1n _ m1 )= 2( mmn− n ) × 5( mmn− n )
4
You should already know how to:
1 1 a 2 2 e 3
7
5
8 Student’s own answers 3
1 2
9 a 27
b 12
c
1 10 a x = 3
b x = 2
c x = 27
b 5
c 9
5
11 a 59
d
12 5 4 5
2
d 1
e 26 × 33 = 1728 12 Mathematics is as old as man.
Answers 201092_answers.indd 1
1 05/03/21 9:32 AM
E1.2
Mixed practice
You should already know how to:
1 a 35 ≤ x < 45 b 65 ≤ x < 75 c 115 ≤ x < 125
1 a 5200 b 23.961 c 18.24 2 a –4
–2
2
4
b –2
0
–1
0
1
2
3
c –5
–4
–3
–2
–1
0
1
3 a 424.3 b 0.001125 c 98.231 d 5.236
Practice 1 1 1.55 m ≤ length of wood < 1.65 m 2 375 kg ≤ mass of crate < 425 kg 3 59.5 m ≤ length of rope < 60.5 m 4 55 km ≤ length of island of Mauritius < 65 km 5 It is acceptable since ‘within 3 mm of 7 cm’ means that 67 mm < h < 73 mm. 6 The card may not fit in the envelope. 9.45 cm ≤ length of card < 9.55 cm and 9.5 cm ≤ length of envelope < 10.5 cm. The card will not fit if its length is greater than the length of the envelope, which happens when 9.5 cm ≤ length of envelope < length of card < 9.55 cm 7 21.5 kg ≤ mass < 22.5 kg 12.55 cm ≤ length < 12.65 cm 2.035 cm3 ≤ volume < 2.045 cm3 0.65 tonnes ≤ mass < 0.75 tonnes 132.5 cm ≤ height < 133.5 cm 51 500 m2 ≤ area < 52 500 m2 58.65° ≤ temperature < 58.75°
2 a 1.5 ≤ x < 2.5 b 16.5 ≤ x < 17.5 c −85.5 ≤ x < −84.5 3 a 12.45 cm ≤ x < 12.55 cm b 21.65 cm ≤ x < 21.75 cm c 34.75 cm ≤ x < 35.85 cm d 52.05 cm ≤ x < 52.15 cm e 80.35 cm ≤ x < 80.45 cm 4 a 458 m ≤ perimeter < 462 m b 12 210.25 m2 ≤ area < 12 440.25 m2 5 3.76 cm ≤ side length ≤ 4.26 cm 6 12.16 km/liter 7 0.027 8 a 14.6 c 52.4 e 14.8 g 53.9
b 1.8 d 1.28 f 2 h 1.31
Review in context 1 a 6850 km ≤ radius of satellite’s orbit < 6900 km b 43 332 km c 314 km 2 22 fuel tanks are needed, since it needs a minimum of 21.66 fuel tanks (21 is therefore not enough). 3 a 229 days (the actual time is 228.4 days, but it would not have reached Mars after only 228 days). b 252.9 days rounded to 253 days.
Practice 2 1 34 boxes 2 34 cm ≤ perimeter of photoframe < 34.4 cm 3 59.9 m ≤ perimeter of garden < 62.1m, and 193.725 m2 ≤ area of garden < 205.325 m2 4 25 minutes 5 She can fill between 10 and 12 full glasses.
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Answers 05/03/21 9:32 AM
Unit 2 Answers
Practice 3
E2.1 You should already know how to: 1 a 6 < 8, valid c 6 < 12, valid
b 2 < 4, valid d −3 < −6, not valid
2 a x = 2, addition and multiplication principles. b x = 12, addition and multiplication principles. 3 a x > 3 c x≥3
b x < 2 d −2 < x < 2
4 a
y 5 4 3 1 −4 −3 −2 −1 0 −1
2
1
−2
3
6 5
−4
3
4 3
x + 2y = 6
2
2
1
1 −2 −1 0 −1
1 2 3 4 5 6 7 8 9 10 x
7
4 x
y = 3x − 2
−3 y 4
−4 −3 −2 −1 0 −1 −2 −3 −4 −5 −6 −7 y b 8
2
b
1 The unshaded area is the solution set. a y 7 6 5 4 3 2 1
1
2
3
4
5
6
7 x
0
Practice 1
17
0
Practice 2
−4
1 Solutions the same as in Practice 1
−5
2 y ≥ 6 − x and y > 4
−6
3 3x + 2 < 9x + 6 −6x < 4
−7
which is an infinite set of solutions.
4
5
6
7
x
8
1
2
3
4
5
6
7
8 x
−2
−2 3
3
−1
7 a > 4 8 b ≤ 1.25 9 k ≤ 6.4
x>
2
c y
1 x < 4 2 x > 54 3 m < 1 4 x ≥ 8 7 5 x ≥ 2 6 x < −
1
−3
−8 d
y 4 3 2 1
−4 −3 −2 −1 0 −1
1
2
3
4
x
−2 −3 −4
Answers 201092_answers.indd 3
3 05/03/21 9:32 AM
e
2 x < 6; y ≤ x; y ≥ 6 − 2x
y 4
3 The unshaded area is the solution set. a y 6
3 2
5
1
4
−4 −3 −2 −1 0 −1
1
2
3
4
x
3 2
−2
1
−3
0 −6 −5 −4 −3 −2 −1 −1
−4
1
2
3
4
x
1
2
3
4
5
y 6
b
5
−2
4
−3
3
−4
2
y 4
1
3
−6 −5 −4 −3 −2 −1 0 −1
2
−2
1
−3 −3
−4 −3 −2 −1 0 −1
1
2
3
4
6
x
−4 −4
x
−5 −5
−2
−6 − 6
−3
4 The unshaded area is the solution set. a y
−4
8
y
7 6
1.4
5
1.2
4
1
3
0.8
2
0.6
1
0.4
−4 −3 −2 −1 0 −1
0.2 0.1 0.2 0.3
−0.4
201092_answers.indd 4
6 x
−6
−4 −3 −2 −1 0 −1
4
5
−5
1
−0.3−0.2−0.10
4
−4
2
h
3
−3
3
g
2
−2
y 4
f
1
x
1
2
3
4
5
6
7
8
x
−2 −3 −4
Answers 05/03/21 9:32 AM
b
d y 20
y 30 28
18
26
16
24
14
22
12
20
10
18 16
8
14
6
12
4
10
2
8
−2 0 −2
6 4
c
4
6
8
10
−6 2
4
6
8 10 12
x
−8
−4
−10
−6
−12 −14
y 16
−16
14
−18
12
−20
10
−22
8
−24
6
−26
4
Practice 4
2
1 Maximum = 780 at (15, 1.5)
−6 −4 −2 0 −2 −4
x
−4
2 0 −6 −4 −2 −2
2
2
4
6
8
10 12 14 16
x
2 Maximum = 19.6 at (1, 6) 3 Maximum = 707 at (99, 181)
−6
4 The manufacturer should make 105 mid-top shoes and 45 high-top shoes, which would make a profit of $2085 per day.
−8
5 6 small and 6 large minibuses
−10
6 100 algebraic solvers and 170 graphing programs
−12
7 $640 (from 40 downhill skis and 30 cross-country skis)
−14
8 $75 000 in municipal bonds and $25 000 in bank mutual fund
−16
Answers 201092_answers.indd 5
5 05/03/21 9:32 AM
Mixed practice
c y 6
1 a x ≥ 1 b x < 18 c x > −9 d x