The quadratic formula is 

So the solution for k is 16.
Hope that helps!
<h3>Possible coordinates of R = -5 or 5</h3><h3>Possible coordinates of T = -7 or 7</h3>
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Explanation:
If we're on a number line, then R could be at either R = 5 or R = -5. This is so the distance from A to R is 5 units. Distance is never negative. You count out the spaces to get the distance, or use subtraction and absolute value.
Saying "distance from A to R is 5" can be written as AR = 5. Meaning segment AR is 5 units long.
Now if AT = 7, then T could be at 7 or -7 on the number line. The reasoning as similar as to why R could be at -5 or 5.
Answer:
{ x | -3 <= x < +1 }
Step-by-step explanation:
We note that the graph occupies from x=-3 to x=+1, while -3 is a value included (endpoint is solid), and +1 is excluded (endpoint hollow).
Thus the domain is { x | -3 <= x < +1 }
The answer would be 2 miles.