2.47 + 7.1
7.1 + 2.47
9.57-7.1
9.57-2.47
Answer:
The distance of the plane from the base of the tower is 25.5 foot.
Step-by-step explanation:
As given
Max is in a control tower at a small airport.
He is located 50 feet above the ground when he spots a small plane on the runway at an angle of depression of 27°.
Now by using the trigonometric identity.

As shown in the figure given below
Perpendicular = CB
Base = AC = 50 feet

Put in the identity.



Put in the above

CB = 0.51 × 50
CB = 25.5 foot
Therefore the distance of the plane from the base of the tower is 25.5 foot.
4.7
It just is.....
It is what it is.....
Step 1: Convert
, which is in radians into degrees. To convert it multiply by 

900/12
75
Step 2: 75 degrees isn't on the unit circle but 45 degrees and 30 degrees is. Since 45 + 30 = 75 you can use the cosine of 45 and 30 to find the exact value
cos45 = 
cos30 =
Step 3: Add the cos45 and cos30 to get cos5pi/12

Hope this helped!