SOLUTION: Find all points having an x-coordinate of 4 whose distance from the point (-2,-1) is 10

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Question 989604: Find all points having an x-coordinate of 4 whose distance from the point (-2,-1) is 10
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
The distance formula is,
D=sqrt%28%28x%5B2%5D-x%5B1%5D%29%5E2%2B%28y%5B2%5D-y%5B1%5D%29%5E2%29
Squaring both sides and substituting with known information,
100=%284-%28-2%29%29%5E2%2B%28y-%28-1%29%29%5E2
100=%284%2B2%29%5E2%2B%28y%2B2%29%5E2
100=6%5E2%2B%28y%2B2%29%5E2
%28y%2B2%29%5E2=64
y%2B2=0+%2B-+8
y=-2+%2B-+8
y=-10 and y=6
(4,-10) and (4,6)