Answer:
407.22 foot is the boat from the base of the lighthouse
Step-by-step explanation:
Given the statement: An observer on top of a 50-foot tall lighthouse sees a boat at a 7° angle of depression.
Let x foot be the distance of the object(boat) from the base of the lighthouse
Angle of depression = 
[Alternate angle]
In triangle CAB:
To find AB = x foot.
Using tangent ratio:


Here, BC = 50 foot and 
then;

or


Simplify:
AB = x = 407.217321 foot
Therefore, the boat from the base of the light house is, 407.22'
Answer:
4
Step-by-step explanation:
can also be written as
. Evaluating this gives
=
= 
<span>The two fires are about 70 feet from each other.
The assumption is that the ground is relatively level and that a right triangle will be made with the three points of the triangle being the ranger, the spot on the ground directly beneath the ranger, and the fire itself. So the distance to the first fire will be:
Calculate the angle. That will be 90° - 11.6° = 78.4°
The distance will be
tan(78.4) = X/60
60 tan(78.4) = X
60 * 4.871620136 = X
292.2972082 = X
And that's how far the 1st fire is from the ranger's station. Now for the 2nd
angle = 90° - 9.4° = 80.6°
60 tan(80.6) = X
60 * 6.040510327 = X
362.4306196 = X
And the distance between the two fires will be the difference in distance from the tower, so
362.4306196 - 292.2972082 = 70.13341146
Rounding to 2 significant figures gives 70 feet.</span>
It will take 90 minutes.
Why?
Rene has to go 60 miles.
He takes 1 hour to go 40 miles.
60 miles is 'one and a half' times 40.
So, he needs an hour and a half to go 60 miles.