Year 9

Pythagoras: Finding right-angled triangles

Year 9

Pythagoras: Finding right-angled triangles

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Lesson details

Key learning points

  1. In this lesson, we will learn how to use Pythagoras's theorem to find the height of triangles with and without right angles.

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6 Questions

Q1.
Which side the the hypotenuse of the below triangle?
An image in a quiz
LM
LN
Correct answer: MN
Q2.
The digram shows a right-angled triangle. Which of the statements is correct?
An image in a quiz
Correct answer: A
B
C
D
Q3.
Which equation does NOT relate to the triangle show below?
An image in a quiz
A
B
C
Correct answer: D
Q4.
Work out the length of the hypotenuse of the triangle shown below.
An image in a quiz
14 cm
25 cm
Correct answer: 5 cm
7 cm
Q5.
Find the length of the missing side of the right-angled triangle.
An image in a quiz
2 cm
3 cm
Correct answer: 4 cm
Q6.
Use Pythagoras’ Theorem to determine which of the sets of numbers below are Pythagorean triples:
2, 3, 4
4, 5, 6
Correct answer: 6, 8, 10

7 Questions

Q1.
Which side the the hypotenuse of the below triangle?
An image in a quiz
Correct answer: m
n
p
Q2.
The digram shows a right-angled triangle. What is the length of the hypotenuse?
An image in a quiz
√10 cm
Correct answer: √13
10 cm
13
Q3.
The right-angled triangle ABC has short sides of length 8 cm and 4 cm. Find the length of AC.
An image in a quiz
Correct answer: √80
12 cm
48 cm
80 cm
Q4.
Use Pythagoras’ Theorem to determine which of the sets of numbers below are Pythagorean triples:
2, 3, 4
Correct answer: 3, 4, 5
5, 6, 7
Q5.
Sandra tried to calculate the unknown length. What mistake has she made in Step 1?
An image in a quiz
Correct answer: She did not identify the hypotenuse correctly.
She did not need to square the numbers.
She should have written 6 + 10 = x squared.
Q6.
Sandra tried to calculate the unknown length. What mistake has she made in Step 2?
An image in a quiz
Made a mistake with re arranging the equation.
Mixed up the hypotenuse and shorter side lengths.
Correct answer: She doubled the sides instead of squaring.
Q7.
What do you need to do in order to find the area of the triangle shown below.
An image in a quiz
Find the length of the perpendicular height using Pythagoras then multiply by 32.
Find the length of the perpendicular height using Pythagoras then multiply by 68
Correct answer: Find the length of the perpendicular height using Pythagoras, multiply by 32 then divide by 2.
Multiply 32 x 68 then divide by 2.