Finding variables using the distance equation

Solar_blaze

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Apr 20, 2015
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I always get stuck with a Y variable , it says find a point on the axis of X=2 and its distance from the point (7,1) is the root of 61.
It has two answers (2,7) and (2,-5)
I did 61=(7-2)^2+(1-y)^2
61=25+(1-y)^2
36=(1-y)^2
Root 36=(1-y)^2
6=1-y than y=1-6 . Y=-5 is that correct how do I get the second answer of y=7? Was the calculations right?
 
I always get stuck with a Y variable , it says find a point on the axis of X=2 and its distance from the point (7,1) is the root of 61.
It has two answers (2,7) and (2,-5)
I did 61=(7-2)^2+(1-y)^2
61=25+(1-y)^2
36=(1-y)^2

±√(36) = (1-y)

±6 = 1 - y


y = -5 or 7

Root 36=(1-y)


6=1-y than y=1-6 . Y=-5 is that correct how do I get the second answer of y=7? Was the calculations right?

Alternative (better) way:

(1 - y)^2 - 6^2 = 0

[(1-y) + 6][(1-y) - 6] = 0

[7 - y][-5 - y] = 0 → y = 7 or -5
 
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