Question

How to find the length of AB

Answers


A. 11.62
B. 27.22
C. 19.78
D. 22.02

Answer 1

AB = 19.78

Explanation:

From the diagram (Right-angle triangle):

AC = 16

AB = ?

Angle = 54°

Applying trig ratio:

Tan 54° = 16/BC

1.376381920 = 16/BC

Therefore;

BC = 16/1.376381920

BC = 11.62

To solve the length AB:

Cos 54° = BC/AB

0.587785252 = 11.62/AB

Solving AB gives:

AB = 11.62/0.587785252

AB = 19.78

Answer 2

The answer is option C

Explanation:

To find the length of AB we use sine

sin∅ = opposite / hypotenuse

From the question

The hypotenuse is AB

The opposite is AC

So we have

sin 54 = AC/AB

sin 54 = 16 / AB

AB = 16/sin 54

AB = 19.777

AB = 19.78

Hope this helps you