Answer:

Step-by-step explanation:
Let

We factor 2 to obtain;

We factor the polynomial within the parenthesis by grouping.



We apply difference of two squares on the second factor: 

We now compare to;

It is now obvious that 
We are trying to find the number that when added to 19, gives us less than 42. We can set up this simple inequality:
19 + x < 42
Now, subtract 19 from both sides:
x < 23
Our number can be anything less than 23.
Answer:
relation ( but not a function)
Step-by-step explanation:
Answer:
2.5
Step-by-step explanation:
t = 0.25
Substitute d with 100
t = 0.25 x (
)
A number to the half power is equal to the square root of a number.
Square root of 100 is 10: 
t = 0.25*10
t = 2.5
Hope this helps :)
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