i have a problem that im stuck on, the question is this
from a ship at sea, the angles of elevation of the top and bottom of a vertical lighthouse standing on the edge of a vertical cliff are 31degrees, and 26 degrees respectively. if the light house is 25m high, how high is the cliff?
so far i have h+25/tan31 = h/tan26
rearrange to, (h+25)tan26 = h tan31
im lost after this
any help would be appreciated.
You've done the correct thing so far and I got this, too.
So multiply the bracket:
Move the h terms together:
Factorise the h:
And divide by the bracket ........
thanks for the help!
I divided by the brackets? (I think), meaning I did what was in the brackets first
(tan31-tan26) = 0.1131280305 * h = 25 tan 26
then, divided the first half by 0.1131280305 to move it over and under to get
h = 25 tan 26
0.1131280305 = 107.78332
is this correct, I have a feeling you meant something else by divide by the brackets and now im way off.
all the best
That's spot on; well done!