Finding missing sides using sine and cosine for any angle

Lesson details

Key learning points

1. In this lesson, we will learn how to find missing sides using sine and cosine for any angle in a triangle.

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This content is made available by Oak National Academy Limited and its partners and licensed under Oak’s terms & conditions (Collection 1), except where otherwise stated.

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7 Questions

Q1.
Complete the statement: In a right angled triangle that has an interior angle of 30 degrees, opposite/ hypotenuse = .................
0.2
0.87
Q2.
Complete the statement: In a right angled triangle that has an interior angle of 60 degrees, opposite/ hypotenuse = .................
0.2
0.5
Q3.
Complete the statement: In a right angled triangle that has an interior angle of 60 degrees, adjacent/ hypotenuse = .................
0.2
0.87
Q4.
Complete the statement: In a right angled triangle that has an interior angle of 30 degrees, adjacent/ hypotenuse = .................
0.2
0.5
Q5.
What is the length of side a?
3.4 cm
6 cm
Q6.
What is the length of side b?
10 cm
3.5 cm
Q7.
What is the size of angle a?
45 degrees
60 degrees

7 Questions

Q1.
What is the length of side marked q ?
10 cm
5 cm
Q2.
What is the length of the side marked r ?
15 cm
22 cm
Q3.
What is the correct step for calculating the length of side b?
Option 2
Option 3
Q4.
What is the length of of b correct to 1 decimal place?
0.86 cm
10 cm
Q5.
What is the correct step for calculating the length of side a?
Option 1
Option 2
Q6.
What is the length of a, correct to 1 decimal place?
0.5 cm
23 cm