Everything Maths Grade 10

25 ◦

7

x

y

SOLUTION

Step 1: Identify the opposite and adjacent sides and the hypotenuse with reference to the given angle

tan=

opposite

adjacent

tan 25 °=

x

7

cos=

adjacent

hypotenuse

cos 25 °=

7

y

Step 2: Rearrange the equations to solve forxandy

x= 7tan 25 °

y=

7

cos 25 °

Step 3: Use your calculator to find the answers

x=3,26415...

x3,26

y=7,72364...

y7,72

VISIT:

The following video shows an example of finding unknown lengths in a triangle using the trigonometric ratios.

See video:2FQTatwww.everythingmaths.co.za

Chapter 5. Trigonometry 123