Answer:
c
Step-by-step explanation:
The complete question in the attached figure
we know that
in the triangle BDC
cos alfa=3/y----------> equation 1
sin alfa=x/y----------> equation 2
in the triangle ABD
cos alfa=4/5--------> equation 3
sin alfa=3/5---------> equation 4
then
Equal equation 1 and 3
3/y=4/5---------> y/3=5/4----------> y=15/4
Equal equation 2 and 4
x/y=3/5-------> x=3*y/5------------> 3*15/(4*5)-----> x=9/4
the answer is
<span>x=9/4 y=15/4</span>
Answers:
Functions
- y = -x+11
- y = 2x^2-6x+4
- y = -7
Not functions
- x = 3
- x^2+y^2 = 81
- y^2 = -5x-12
=======================================================
Explanation:
A function is possible if and only if any given x input leads to exactly one y output.
For something like x^2+y^2 = 81, we can see that x = 0 leads to either y = 9 or y = -9. So this would <u>not</u> be a function. We would need x to pair with only y value to have it be a function.
We have the same thing going on with y^2 = -5x-12 as well.
For anything of the form x = k, where k is any real number, this is also not a function. We have one single input only and it leads to infinitely many outputs. So in a sense, this is even worse compared to the other examples.
-----------------
In summary, we have these three non-functions:
- x = 3
- x^2+y^2 = 81
- y^2 = -5x-12
Everything else is a function. You can use the vertical line test as a visual way to check.
Transitive.
Associative is (a + b) + c = a + (b + c)
Commutative is a + b = b + a
Reflexive is a = a
Thus, transitive is the correct answer.
Hope this helps!
Answer:
Explained below.
Step-by-step explanation:
The random variable <em>X</em> is defined as the number of stars in a given volume of space.

The probability mass function of <em>X</em> is:

(7)
Compute the probability of exactly two stars in 16 cubic light-years as follows:

(8)
Compute the probability of three or more stars in 16 cubic light-years as follows:

(9)
In 16 cubic light years there is only 1 star.
Then in 1 cubic light years there will be, (1/16) stars.
Then in 4 cubic light years there will be, 4 × (1/16) = (1/4) stars.
(10)
In 16 cubic light years there is only 1 star.
Then in 1 cubic light years there will be, (1/16) stars.
Then in <em>t</em> cubic light years there will be, [<em>t</em> × (1/16)] stars.