To solve this problem you must apply the proccedure shown below:
1. You have that
varies jointly as
and
and inversely as the product of
and
. Therefore, you can write the following equation, where
is the constant of proportionality:

2. Now, you must solve for the constant of proportionality, as following:

3. Susbtiute values:


4. Substitute the value of the constant of proportionality into the equation:

The answer is: 
Answer:
Verified below
Step-by-step explanation:
We want to show that (Cos2θ)/(1 + sin2θ) = (cot θ - 1)/(cot θ + 1)
In trigonometric identities;
Cot θ = cos θ/sin θ
Thus;
(cot θ - 1)/(cot θ + 1) gives;
((cos θ/sin θ) - 1)/((cos θ/sin θ) + 1)
Simplifying numerator and denominator gives;
((cos θ - sin θ)/sin θ)/((cos θ + sin θ)/sin θ)
This reduces to;
>> (cos θ - sin θ)/(cos θ + sin θ)
Multiply top and bottom by ((cos θ + sin θ) to get;
>> (cos² θ - sin²θ)/(cos²θ + sin²θ + 2sinθcosθ)
In trigonometric identities, we know that;
cos 2θ = (cos² θ - sin²θ)
cos²θ + sin²θ = 1
sin 2θ = 2sinθcosθ
Thus;
(cos² θ - sin²θ)/(cos²θ + sin²θ + 2sinθcosθ) gives us:
>> cos 2θ/(1 + sin 2θ)
This is equal to the left hand side.
Thus, it is verified.
Answer:
2 units
Step-by-step explanation:
The given equation of the circle is:

The general equation of the circle is:

Comparing the given equation with the general equation we can say:
g = 4
f = -3
c = 21
The formula for radius of the circle is:

Using these values of the given circle, we get:

Therefore, the length of radius of the given circle is 2.
He made $40 those 5 days.
8•5=40
Answer:
y = 2x - 1
Step-by-step explanation: