Year 9

Year 9

The sine and cosine ratios for 30 and 60 degrees

Lesson details

Key learning points

1. In this lesson, we will learn how to find missing sides and angles in triangles using sine and cosine for 30 and 60 degrees.

Licence

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7 Questions

Q1.
Fill in the gaps: In a right-angled triangle, the ratio of the length of the side adjacent side to the length of the hypotenuse called the ...................
hypotenuse
sine ratio
Q2.
What is the sine ratio of a right angled triangle with angle 30 degrees?
0.2
0.87
Q3.
Which image shows the sides of the triangle correctly labelled (in relation to angle a)?
Option 2
Option 3
Q4.
Complete the following: sine 30 = ..............
cosine 30
sine 60
Q5.
Make y the subject.
Option 1
Option 3
Q6.
b = 14 cm when 𝑥 = ?
15 degrees
30 degrees
Q7.
What is the length of the hypotenuse?
17 cm
4.5 cm

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?