# Surds and triangles

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## Lesson details

### Key learning points

1. In this lesson, we will recap how to use Pythagorean theorem to find the length of missing sides in triangles leaving the answers is surd form.

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## Video

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## Worksheet

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## Starter quiz

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### 6 Questions

Q1.
√9 is a surd
Option 3
Option 4
Option 5
True
Q2.
Which of the following is a surd
A
B
D
Q3.
Which on the following is NOT a surd
B
C
D
Q4.
Which of the following is a surd?
A
B
D
Q5.
Evaluate √49
24.5
98
Q6.
Estimate √57
28.2
28.5
7.2

## Exit quiz

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### 7 Questions

Q1.
Which of the following is a surd
A
C
D
Q2.
Which of the following is NOT a surd
Option 1
B
C
Q3.
Evaluate √144
1.44
72
Q4.
A right- angled triangle has sides a, b and c as show in the diagram. What is the correct formula to find the length a.
A
B
C
Q5.
A right- angled triangle is shown in the diagram below. Find the length of the hypotenuse.
116
14
28
Q6.
A right- angled triangle is shown int he diagram below. Find the length of the missing side.
√135
√33
153
Q7.
A right- angled triangle is shown int he diagram below. Find the length of the missing side.
√146