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Test1

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Test 1
Question 1
Factorise the following:
6π‘₯ + 24
…………………………
Question 2
Factorise the following:
π‘₯2 + 2π‘₯
…………………………
Question 3
Factorise the following quadratic:
π‘₯2 + 10π‘₯ + 21
…………………………
Question 4
Factorise the following quadratic:
π‘Ž2 − 7π‘Ž + 10
…………………………
Question 5
Factorise the following quadratic:
𝑙2 + 2𝑙 − 3
…………………………
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Question 6
Make π‘₯ the subject of 10𝑦 =
5𝑧+10𝑀
9π‘₯
π‘₯ = …………………………
Question 7
The ratio (𝑦 + π‘₯): (𝑦 − π‘₯) is equivalent to π‘˜: 1.
Find an expression for 𝑦 in terms of π‘˜ and π‘₯.
𝑦 = …………………………
Question 8
Make π‘₯ the subject of the formula where π‘₯ is positive:
2π‘₯ − 4𝑧π‘₯ = 5𝑒
π‘₯ = …………………………
Question 9
Make π‘₯ the subject of the formula where π‘₯ is positive:
(π‘₯ − 3𝑦) = 4π‘₯𝑧 + 3𝑒
π‘₯ = …………………………
Question 10
Expand and simplify
−7 + 6(5π‘₯ − 8)
…………………………
Question 11
Expand
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9𝑦(4𝑦 + 7)
…………………………
Question 12
Expand and simplify
2(3π‘₯ − 4) + 4(5π‘₯ − 2)
…………………………
Question 13
Expand and simplify
2(5π‘₯ − 1) − 2(π‘₯ + 5)
…………………………
Question 14
Expand and simplify
−4 − (4π‘₯ + 3)
…………………………
Question 15
Expand and simplify
2π‘₯(π‘₯ + 1) + π‘₯(2π‘₯ + 3)
…………………………
Question 16
[AQA GCSE Nov 2013 1H Q15a]
Expand and simplify
(2π‘₯ + 1)(3π‘₯ − 4)
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…………………………
(2 marks)
Question 17
Expand and simplify
(π‘₯ − 10)(π‘₯ + 10)
…………………………
Question 18
Expand and simplify
(π‘₯ + 3)(π‘₯ − 5)
…………………………
Question 19
Expand and simplify:
(π‘₯ − 4 )2
…………………………
Question 20
Expand and simplify
(2π‘₯ + 3)(π‘₯ + 6)
…………………………
Question 21
Given that
Angle 𝐴 : Angle 𝐡 = 2: 7
determine the value of 𝑦 in the diagram.
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Give your answer correct to 1 decimal place.
𝑦 = ………………………… cm
Question 22
The distance between the top of a building and a point 𝑃 on the ground is 13 m and the
angle of elevation is 59° from the point 𝑃 to the top of the building.
Find the height of the building. Give your answer correct to 1 decimal place.
β„Ž = ………………………… m
Question 23
Determine the area of the triangle in the diagram.
Give your answer correct to 1 decimal place.
………………………… cm 2
Question 24
Determine whether it is possible to construct the triangle with the lengths and angles given
in the diagram below.
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The triangle can be constructed. [ ]
The triangle can not be constructed. [ ]
Question 25
𝑃𝑄𝑅 is an isosceles triangle where 𝑃𝑄 = 𝑄𝑅.
Work out the length marked 𝑧 on the diagram.
Give your answer correct to 1 decimal place.
𝑧 = ………………………… cm
Question 26
The diagram below shows the isosceles triangle π‘‹π‘Œπ‘ .
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Find the area of triangle π‘‹π‘Œπ‘ .
Give your answer to 1 decimal place.
………………………… cm 2
Question 27
The diagram below shows the isosceles triangle 𝑃𝑄𝑅 .
The area of triangle 𝑃𝑄𝑅 is 270 cm 2 .
Find the perimeter of triangle 𝑃𝑄𝑅 .
………………………… cm
Question 28
From point 𝐷, Anna walks 80 m due south to point 𝐸.
From 𝐸, she then walks 140 m due east to point
𝐹.
Work out the length of 𝐷 𝐹. Round your answer to 1 decimal place.
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………………………… m
Question 29
Tim makes a framework from metal rods.
The framework is in the shape of the right-angled triangle π‘‹π‘Œπ‘ shown in the diagram
The rods that Tim uses to make the framework have a weight of 1 kg per metre.
Work out the total weight of the framework.
Give your answer, in kg, correct to 1 decimal place.
………………………… kg
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Mark scheme
Question 1
6(π‘₯ + 4)
Question 2
π‘₯(π‘₯ + 2)
Question 3
(π‘₯ + 7)(π‘₯ + 3)
We find two numbers that add together to give 10 and multiply together to give 21. These
are 7 and 3. Using these, we factorise as follows:
π‘₯2 + 10π‘₯ + 21 = (π‘₯ + 7)(π‘₯ + 3)
Question 4
(π‘Ž − 2)(π‘Ž − 5)
We find two numbers that add together to give 7 and multiply together to give 10. These
are 2 and 5. Using these, we factorise as follows, being very careful to keep track of minus
signs:
π‘Ž2 − 7π‘Ž + 10 = (π‘Ž − 2)(π‘Ž − 5)
Question 5
(𝑙 − 1)(𝑙 + 3)
We find two numbers that have difference 2 and multiply together to give 3. These are 1
and 3. Using these, we factorise as follows, being very careful to keep track of minus signs:
𝑙2 + 2𝑙 − 3 = (𝑙 − 1)(𝑙 + 3)
Question 6
5𝑧+10𝑀
90𝑦
βž€ Make π‘₯ the subject.
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5𝑧+10𝑀
10𝑦 = 9π‘₯
× 9π‘₯ ↓
↓ × 9π‘₯
90π‘₯𝑦 = 5𝑧 + 10𝑀
÷ 90𝑦 ↓
↓ ÷ 90𝑦
5𝑧+10𝑀
π‘₯ = 90𝑦
Question 7
π‘₯(π‘˜+1)
π‘˜−1
Question 8
5𝑒
2−4𝑧
You need to factorise by π‘₯ first, and then divide by the bracket.
2π‘₯ − 4𝑧π‘₯ = 5𝑒
π‘₯(2 − 4𝑧) = 5𝑒
÷ (2−4𝑧) ↓
↓ ÷ (2−4𝑧)
5𝑒
π‘₯ = 2−4𝑧
5𝑒
∴ π‘₯ = 2−4𝑧
Question 9
3𝑒+3𝑦
1−4𝑧
You need to expand the bracket, put π‘₯ on the left hand-side, factorise by π‘₯, and then divide
by the bracket.
(π‘₯ − 3𝑦) = 4π‘₯𝑧 + 3𝑒
π‘₯ − 3𝑦 = 4π‘₯𝑧 + 3𝑒
π‘₯ − 4π‘₯𝑧 = 3𝑒 + 3𝑦
π‘₯(1 − 4𝑧) = 3𝑒 + 3𝑦
÷ (1−4𝑧) ↓
↓ ÷ (1−4𝑧)
3𝑒+3𝑦
π‘₯ = 1−4𝑧
∴ π‘₯=
3𝑒+3𝑦
1−4𝑧
Question 10
30π‘₯ − 55
βž€ Expand the bracket.
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−7 + 6(5π‘₯ − 8)
= −76 × 5π‘₯ + 6 × −8
= −7 + 30π‘₯ − 48
➁ Collect like terms and simplify.
−7 + 30π‘₯ − 48
= 30π‘₯ − 7 − 48
= 30π‘₯ − 55
Question 11
36𝑦2 + 63𝑦
βž€ Multiply all terms in the bracket by 9𝑦, and then simplify.
9𝑦(4𝑦 + 7) = 9𝑦 × 4𝑦 + 9𝑦 × 7
= 36𝑦2 + 63𝑦
Question 12
26π‘₯ − 16
βž€ Expand each bracket.
2(3π‘₯ − 4) + 4(5π‘₯ − 2)
= 6π‘₯ − 8 + 20π‘₯ − 8
➁ Collect like terms and simplify.
6π‘₯ − 8 + 20π‘₯ − 8
= 6π‘₯ + 20π‘₯ − 8 − 8
= 26π‘₯ − 16
Question 13
8π‘₯ − 12
βž€ Expand each bracket.
2(5π‘₯ − 1) − 2(π‘₯ + 5)
= 10π‘₯ − 2 − 2π‘₯ − 10
➁ Collect like terms and simplify.
10π‘₯ − 2 − 2π‘₯ − 10
= 10π‘₯ − 2π‘₯ − 2 − 10
= 8π‘₯ − 12
Question 14
−4π‘₯ − 7
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βž€ Expand the bracket.
= −4 − (4π‘₯ + 3)
= −4 − 1 (4π‘₯ + 3)
= −4 − 4π‘₯ − 3
➁ Collect like terms and simplify.
= −4 − 4π‘₯ − 3
= −4π‘₯ − 4 − 3
= −4π‘₯ − 7
Question 15
4π‘₯2 + 5π‘₯
βž€ Expand each bracket.
2π‘₯(π‘₯ + 1) + π‘₯(2π‘₯ + 3)
= 2π‘₯2 + 2π‘₯ + 2π‘₯2 + 3π‘₯
➁ Collect like terms and simplify.
2π‘₯2 + 2π‘₯ + 2π‘₯2 + 3π‘₯
= 2π‘₯2 + 2π‘₯2 + 2π‘₯ + 3π‘₯
= 4π‘₯2 + 5π‘₯
Question 16
6π‘₯2 − 5π‘₯ − 4
Question 17
π‘₯2 − 100
βž€ Multiply each term in the first bracket by each term in the second bracket.
(π‘₯ − 10)(π‘₯ + 10)
= π‘₯ × π‘₯ + π‘₯ × 10 − 10 × π‘₯ − 10 × 10
= π‘₯2 + 10π‘₯ − 10π‘₯ − 100
➁ Simplify.
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= π‘₯2 − 100
Question 18
π‘₯2 − 2π‘₯ − 15
βž€ Multiply each term in the first bracket by each term in the second bracket.
(π‘₯ + 3)(π‘₯ − 5)
= π‘₯×π‘₯−π‘₯×5+3×π‘₯−3×5
= π‘₯2 − 5π‘₯ + 3π‘₯ − 15
➁ Simplify.
= π‘₯2 − 2π‘₯ − 15
Question 19
π‘₯2 − 8π‘₯ + 16
βž€ Multiply each term in the first bracket by each term in the second bracket.
(π‘₯ − 4 )2
= (π‘₯ + −4)(π‘₯ + −4)
= π‘₯ × π‘₯ + π‘₯ × −4 + −4 × π‘₯ + −4 × −4
= π‘₯2 − 4π‘₯ − 4π‘₯ + 16
➁ Simplify.
= π‘₯2 − 8π‘₯ + 16
Question 20
2π‘₯2 + 15π‘₯ + 18
βž€ Multiply each term in the first bracket by each term in the second bracket.
(2π‘₯ + 3)(π‘₯ + 6)
= 2π‘₯ × π‘₯ + 2π‘₯ × 6 + 3 × π‘₯ + 3 × 6
= 2π‘₯2 + 12π‘₯ + 3π‘₯ + 18
➁ Simplify.
= 2π‘₯2 + 15π‘₯ + 18
Question 21
𝑦 =32.2cm
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βž€ Find the angle 𝐴.
𝐴 = 90 ×
𝐴 = 20
2
2+7
➁ Label the sides.
βž‚ Decide the trigonometric ratio to use.
SOH CAH TOA
Therefore we use tan
βžƒ Write an equation and solve.
tan(πœƒ) =
tan(20) =
𝑦 =
𝑂
𝐻
11
𝑦
11
tan(20)
= 32.2 cm
Question 22
β„Ž =11.1 m
βž€ Draw a diagram.
➁ Draw a triangle and label the sides.
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βž‚ Decide the trigonometric ratio to use.
SOH CAH TOA
Therefore we use sin
βžƒ Write an equation and solve.
sin(πœƒ) =
𝑂
𝐻
β„Ž
13
sin(59) =
β„Ž = 13 sin(59)
= 11.1 m
Question 23
32.8cm 2
βž€ Label the sides.
➁ Decide the trigonometric ratio to use to find the unknown short edge length.
SOH CAH TOA
Therefore we use tan
βž‚ Find the length of the unknown short edge.
tanπœƒ =
𝐴 =
𝑂
𝐴
𝑂
tanπœƒ
9
tan51
=
= 7.288 …
βžƒ Find the area.
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Area =
=
=
height × base
2
7.288… × 9
2
32.8 cm2
Question 24
The triangle can not be constructed.
βž€ Find the values of 𝐴𝐡2 , 𝐡𝐢2 and 𝐴𝐢2 .
𝐴𝐡2 = 1.52
= 2.25
𝐡𝐢2 = 10.52
= 110.25
𝐴𝐢2 = 112
= 121
➁ Compare the value of 𝐴𝐡2 +𝐡𝐢2 with the value of 𝐴𝐢2 .
(Could not display math)
Therefore, by the converse of Pythagoras' theorem, the triangle with the given lengths and
angle can not be constructed.
Question 25
𝑧 =4cm
The isosceles triangle can be split along its height to give a right-angle triangle on both sides.
Using Pythagoras' theorem,
𝑧2 =
=
=
𝑧=
𝑧=
3.72 + 1.52
13.69 + 2.25
15.94
√15.94
4 cm
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Question 26
145.2cm 2
βž€ Use the line of symmetry of the isosceles triangle to draw a right-angled triangle, with the
right angle at the midpoint of π‘‹π‘Œ.
➁ Use Pythagoras' Theorem to find the missing side in this triangle.
π‘€π‘Œ 2 = 18 2 − 9.5 2
= 233.75
𝑀 π‘Œ = 15.2889 … π‘π‘š
βž‚ Find the area of triangle π‘‹π‘Œπ‘.
π΄π‘Ÿπ‘’π‘Ž =
1
2
× 19 × 15.2889 …
= 145.2444 … π‘π‘š 2
βžƒ Round the answer to one decimal place.
π΄π‘Ÿπ‘’π‘Ž = 145.2 π‘π‘š 2
Question 27
75cm
βž€ Find the base of triangle 𝑃𝑄𝑅.
1
2
× π‘ƒπ‘„ × 22.5
×2 ↓
𝑃𝑄 × 22.5
÷ 22.5 ↓
𝑃𝑄
= 270
↓ ×2
= 540
↓ ÷ 22.5
= 24 π‘π‘š
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➁ Use the line of symmetry of the isosceles triangle to draw a right-angled triangle, with the
right angle at the midpoint, 𝑀, of 𝑃𝑄.
βž‚ Use Pythagoras' theorem to find the hypotenuse in this triangle.
π‘₯ 2 = 12 2 + 22.5 2
= 650.25
π‘₯ = 25.5 π‘π‘š
βžƒ Add together all the sides of triangle 𝑃𝑄𝑅.
π‘ƒπ‘’π‘Ÿπ‘–π‘šπ‘’π‘‘π‘’π‘Ÿ = 24 + 2 × 25.5
= 75 π‘π‘š
Question 28
161.2m
βž€ Draw a diagram showing Anna's journey.
➁ Use Pythagoras' theorem to find the length of 𝐷𝐹.
𝐷𝐹 2 = 80 2 + 140 2
= 26000
𝐷𝐹 = 161.2452 … π‘š
βž‚ Round the answer to 1 decimal place.
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𝐷𝐹 = 161.2 π‘š
Question 29
14.2kg
βž€ Use Pythagoras' theorem to find the length 𝑋𝑍.
𝑋 𝑍 2 = 2.9 2 + 5.32
= 36.5
𝑋 𝑍 = 6.0415 …
➁ Find the total length of all the rods in the framework.
π‘‘π‘œπ‘‘π‘Žπ‘™ π‘™π‘’π‘›π‘”π‘‘β„Ž = π‘‹π‘Œ + π‘Œπ‘ + 𝑋𝑍
= 2.9 + 5.3 + 6.0415 …
= 14.2415 …
βž‚ Multiply the total length the weight per metre.
π‘‘π‘œπ‘‘π‘Žπ‘™ π‘€π‘’π‘–π‘”β„Žπ‘‘ = 14.2415 … × 1
= 14.2415 …
βžƒ Round this value to one decimal place.
= 14.2 π‘˜π‘”
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