Question

Help with trigonometry? Will medal :)

An observer (O) spots a bird flying at a 55° angle from a line drawn horizontal to its nest. If the distance from the observer (O) to the bird (B) is 15,000 ft., how far is the bird (B) from its nest (N)? Round to the nearest whole number. (picture coming!)

Answer 1

hello again ^^ I think this is the last question I have

Answer 2

well, same as before
\(sin(\theta)=\cfrac{opposite}{hypotenuse}
\qquad \qquad
% cosine
cos(\theta)=\cfrac{adjacent}{hypotenuse}

\\ \quad \\
% tangent
tan(\theta)=\cfrac{opposite}{adjacent}\)

you'd need one identity that includes ONLY
the adjacent side
hypotenuse
and angle

Answer 3

\(\bf cos(\theta)=\cfrac{adjacent}{hypotenuse}\implies hypotenuse\cdot cos(\theta)=adjacent
\\ \quad \\
15,000\cdot cos(55^o)=x\)

Answer 4

the angle is in Degrees, so make sure your calculator is in Degree mode

Answer 5

Sorry I've been afk >.>
Yes, I used cos on degree mode and got 26151.7019343. I think I should divide it by two but not quite sure o.o

Answer 6

Oh, I got 8604 and that's one of my answer choices. Thank you! One question - how do I know when to multiply and when to divide?