Question

If 8 tan theta =15 find cos theta

Answer 1

tan theta is 15/8 ( tan theta =p/b) h=225+64=289 under root of 17 cos theta is b/h =8/15

Answer 2

$\tan(\theta) =\dfrac{opp}{adj}$

$8 \tan(\theta) =15$

$\tan(\theta) =\dfrac{15}{8}$

Find the hypotenuse:

a² + b² = c²

c² = 15² + 8²

c² = 289

c = √289

c = 17

Find cos theta:

$\cos (\theta) =\dfrac{adj}{hyp}$

$\cos (\theta) =\dfrac{8}{17}$

Answer: cos theta is 8/17