Answer:
D
Step-by-step explanation:
You just need to calculate it as usual. Might as well do in fraction form for clearer understandings
There are 2 chances out of 6 to win $3
Every 6 rolls you are expected to win $6
Every 3 rolls you are expected to win $3.
On average, even though it's impossible, every roll you would make $1.
The first step for solving this problem is to multiply both sides of the bottom equation by -3.

Add the two equations together.
6x - 9y - 6x + 9y = 16 - 21
Eliminate the opposites.
-9y + 9y = 16 - 21
Remember that the sum of two opposites equals 0,, so the equation becomes the following:
0 = 16 - 21
Calculate the difference on the right side of the equation.
0 = -5
This means that the statement

is false for any value of x and y. That means that the answer to your question is (x,y) ∈ ∅,, or no solution.
Let me know if you have any further questions.
:)
Answer: (b) exactly one plane contains a given line and a point not on the line.
Step-by-step explanation: The basic postulates of geometry are very-well known to all of us. For example-
(i) The intersection of two lines determines a point,
(ii) Two parallel lines give result to a plane,
(iii) A line and a point not on the line determines a plane, etc...
Thus, with the help of the third point, we can easily arrive at the conclusion that a given line and a point not lying on the line is contained in a plane. For example- see the attached figure, AB is a line and P is any point not on the line. They both contained in the plane ABC.
Hence, the correct option is (b).