Answer:
see explanation
Step-by-step explanation:
Given
tan a = [tex]\frac{9}{40}[/tex] = [tex]\frac{opposite}{adjacent}[/tex]
We require the hypotenuse h
Using Pythagoras' identity
h² = 9² + 40² = 81 + 1600 = 1681 ( take square root of both sides )
h = [tex]\sqrt{1681}[/tex] = 41 , thus
sin a = [tex]\frac{opposite}{hypotenuse}[/tex] = [tex]\frac{9}{41}[/tex]
cos a = [tex]\frac{adjacent}{hypotenuse}[/tex] = [tex]\frac{40}{41}[/tex]