12 out of 20
Your answer is the question
Answer: 
Step-by-step explanation:
By definition, a relation is a function if and only if each input value has one and only one output value.
For this exercise it is important to remember that thw "Input values" are the values of the variable "x"and the "Output values" are the values of the variable"y".
In this case you have the following function provided in the exercise:

Then, to solve this exercise, you need to follow these steps:
Step 1. You have to substitute
into the function given.
Step 2. Finally, you must evaluate in order to find the corresponding output value (or the value of the variable "y")
You get that this is:

Answer:
This is a educated guess, but x is 80 and y is 100.
Step-by-step explanation:
My logic here is that the triangles are the same because of all the congruent lines and stuff. But from there, you know that both the right and the left side are 40 degrees. You know the total degree of a triangle is 180 so 180 - 40 - 40 is 100. So the final angle is 100. If you look at x, its on the outside, but on a line. If you can imagine a circle, its half, so its a 180 degrees total. Then its 180 = x + 100. So x is 80. And then by that same logic its y = 100.
The distance between is 5
Given: sin theta = 2/5. This tells us that the lengths of the opp side and the hyp are 2 and 5 respectively. The adj side is found using the Pyth. Thm.: 5^2-2^2= 25-4 = 21, so that the adj side is sqrt(21).
The double angle formula for the sine is sin 2theta = 2 sin theta *cos theta.
In this particular problem, the sine of 2theta is 2*(2/5)*[sqrt(21) / 5], or:
(4/25)*sqrt(21).