Answer:
dddddweqwqq
Step-by-step explanation:
Answer:
24.19
Step-by-step explanation:

or the value of x can be 24.20
Answer:
See Below.
Step-by-step explanation:
Problem A)
We have:

When in doubt, convert all reciprocal trig functions and tangent into terms of sine and cosine.
So, let cscθ = 1/sinθ and tanθ = sinθ/cosθ. Hence:

Cancel:

Let 1/cosθ = secθ:

From the Pythagorean Identity, we know that tan²θ + 1 = sec²θ. Hence, sec²θ - 1 = tan²θ:

Problem B)
We have:

Factor out a sine:

From the Pythagorean Identity, sin²θ + cos²θ = 1. Hence, sin²θ = 1 - cos²θ:

Distribute:

Problem C)
We have:

Recall that cos2θ = cos²θ - sin²θ and that sin2θ = 2sinθcosθ. Hence:

From the Pythagorean Identity, sin²θ + cos²θ = 1 so cos²θ = 1 - sin²θ:

Cancel:

By definition:

Answer:
x = 175/7
Step-by-step explanation:
Combining the like terms in 4x-14+3x=161, we get
7x = 175, and so:
x = 175/7
Answer:
10 kph
Step-by-step explanation:
Find the speed of the current of the river.
20/(20 - c) + 180/(20 + c) = 8
20(20 + c) + 180(20 - c) = 8(400 - c^2)
8c^2 - 160c + 800 = 0
8(c^2 - 20c + 100) = 0
8(c - 10)^2 = 0
c = 10
The speed of the current of the river is 10 km/hour.