Temperature is NOT a function of Date
---------------------but-----------------------------
Date IS a function of Temperature
{for explanation of my reasoning, read on...}
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OPTION A:
If it asks "is Y a function of X" then...
...if y has its own x and that x is not shared by a different y, then yes, it's a function.
...if two y's are the same number, but their x's are not the same number as each other, then no, it's not a function.
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EXAMPLE A1:
Date (x) | 17 | 18 | 19 | 20 | 21 | 22 | 23 |
Temp (y) | 63 | 77 | 69 | 73 | 75 | 75 | 70 |
You see how two of the y's are 75?
You see how their x's (21 and 22) are two different numbers?
That means y is NOT a function of x
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EXAMPLE A2:
Date (x) | 17 | 18 | 19 | 20 | 21 | 21 | 23 |
Temp (y) | 63 | 77 | 69 | 73 | 75 | 75 | 70 |
You see how two of the y's are 75?
You see how their x's (21 and 21) are both the same number?
That means y IS a function of x
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OPTION B:
If it asks "is X a function of Y" then...
...if x has its own y and that y is not shared by a different x, then it's yes, a function.
...if two x's are the same number, but their y's are not the same number as each other, then no, it's not a function.
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EXAMPLE B1:
Date (x) | 17 | 18 | 19 | 20 | 21 | 21 | 23 |
Temp (y) | 63 | 77 | 69 | 73 | 74 | 75 | 70 |
You see how two of the x's are 21?
You see how their y's (74 and 75) are two different numbers?
That means x is NOT a function of y
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EXAMPLE B2:
Date (x) | 17 | 18 | 19 | 20 | 21 | 21 | 23 |
Temp (y) | 63 | 77 | 69 | 73 | 75 | 75 | 70 |
You see how two of the x's are 21?
You see how their y's (75 and 75) are both the same number?
That means x IS a function of y