SOLUTION: find x such that the line segment determined by x,-2 and -2,-14 is 13 units long

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Question 1113035: find x such that the line segment determined by x,-2 and -2,-14 is 13 units long
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
The distance between points A%28x%2C-2%29 and B%28-2%2C-14%29 is
d=sqrt%28%28x%5BA%5D-x%5BB%5D%29%5E2%2B%28y%5BA%5D-y%5BB%5D%29%5E2%29%22=%22sqrt%28%28x-%28-2%29%29%5E2%2B%28%28-2%29-%28-14%29%29%5E2%29%22=%22sqrt%28%28x%2B2%29%5E2%2B%28-2%2B14%29%5E2%29=sqrt%28%28x%5E2%2B4x%2B4%29%2B12%5E2%29%22=%22sqrt%28%28x%2B2%29%5E2%2B144%29
You want to find the values for x that make that distance 13 ,
so you want to solve
sqrt%28%28x%2B2%29%5E2%2B144%29=13 or %28x%2B2%29%5E2%2B144=13%5E2 or %28x%2B2%29%5E2%2B144=169 .

%28x%2B2%29%5E2%2B144=169
%28x%2B2%29%5E2=169-144
%28x%2B2%29%5E2=25
x%2B2=%22+%22+%2B-+5
The solution is
system%28x=-2-5%2C%22or%22%2Cx=-2%2B5%29 or highlight%28system%28x=-7%2C%22or%22%2Cx=3%29%29 .
There are two solutions because point B%28-2%2C-14%29
is less than 13 units away from the line y=-2 :