Answer: see proof below
<u>Step-by-step explanation:</u>
Given: A + B + C = π and cos A = cos B · cos C
scratchwork:
A + B + C = π
A = π - (B + C)
cos A = cos [π - (B + C)] Apply cos
= - cos (B + C) Simplify
= -(cos B · cos C - sin B · sin C) Sum Identity
= sin B · sin C - cos B · cos C Simplify
cos B · cos C = sin B · sin C - cos B · cos C Substitution
2cos B · cos C = sin B · sin C Addition
Division
2 = tan B · tan C

<u>Proof LHS → RHS</u>
Given: A + B + C = π
Subtraction: A = π - (B + C)
Apply tan: tan A = tan(π - (B + C))
Simplify: = - tan (B + C)

Substitution: = -(tan B + tan C)/(1 - 2)
Simplify: = -(tan B + tan C)/-1
= tan B + tan C
LHS = RHS: tan B + tan C = tan B + tan C 
To find your sale price you must:

just simply follow that operation and you're good to go
<span>240/6 is 40. so it would be 40 miles per hour (mph)</span>
To solve this problem, we can use the tan function to find
for the distances covered.
tan θ = o / a
Where,
θ = angle = 90° - angle of depression
o = side opposite to the angle = distance of boat from
lighthouse
a = side adjacent to the angle = height of lighthouse = 200
ft
When the angle of depression is 16°18', the initial distance
from the lighthouse is:
o = 200 tan (90° - 16°18')
o = 683.95 ft
When the angle of depression is 48°51', the final distance
from the lighthouse is:
o = 200 tan (90° - 48°51')
o = 174.78 ft
Therefore the total distance the boat travelled is:
d = 683.95 ft - 174.78 ft
<span>d = 509.17
ft</span>
Answer:
The area is 3.9375 cubic ft, so yes, the area will greater than 3 and 1/2 ft.
Hope this helps:)
Step-by-step explanation: