Answer: Choice D
The graph will be discrete because there is no such thing as a partial person to sign up, and the booth is set up once each day for sign ups.
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Explanation:
Let's start with the independent variable d. This acts as the variable x. It's the input. The value of d only takes on positive whole numbers (eg: d = 1, d = 2, d = 3, etc). We cannot have something like d = 2.718
So this bit of evidence shows that our function is discrete. Discrete input values (d) plug into the function to produce corresponding discrete output values (m).
Furthermore, we know that m is discrete because the number of people cannot be a fractional or decimal number. We can't have half a person for instance.
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A quick way to see if a set is discrete or continuous is to ask the question: "is it possible to apply the midpoint formula for ANY two values, and have the output make sense?"
So a set like {1,2,3,4,5,...} is discrete because the midpoint of 2 and 3 is 2.5, but that value is not in the set mentioned.
In other words, discrete sets have "gaps" so to speak, while continuous ones do not.
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Another useful property is that let's say that a < x < b, and x is drawn from the domain set. This reduced set will be finite if we're dealing with discrete data. Eg: The set {1,2,3,4,5,...} has the subset {2,3,4} which is finite and discrete.
In contrast, the subset of real numbers x such that is continuous and this subset is infinitely large (has infinitely many members) because we could have things like 2.718 or 3.14 etc
Given:
The vertices of a parallelogram are P(1,2,1), Q(1,0,-1), R(2,2,0).
PQ and PR are the adjacent sides of the parallelogram.
To find:
The coordinates of vertex S.
Solution:
We know that, the diagonals of a parallelogram bisect each other.
Let the coordinates of the vertex S are (a,b,c).
In the given parallelogram PS and QR are the diagonals. It means their midpoints are same.
On comparing both sides, we get
Similarly,
And,
Hence, the coordinates of vertex S are (2,0,-2).