SOLUTION: How do i find the value of n if the distance between the points at (7,5) and (-3, n) is the square root of 136?

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Question 442101: How do i find the value of n if the distance between the points at (7,5) and (-3, n) is the square root of 136?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+d+=+sqrt%28+%285+-+n%29%5E2+%2B+%28+7+-%28-3%29+%29%5E2%29+
+d+=+sqrt%28+%285+-+n%29%5E2+%2B+10%5E2%29+
+sqrt%28136%29+=+sqrt%28+%285+-+n%29%5E2+%2B+10%5E2%29+
+136+=+%285+-+n%29%5E2+%2B+10%5E2+
+136+=+25+-+10n+%2B+n%5E2+%2B+10%5E2+
+n%5E2+-+10n+-+11+=+0+
+%28n+-+11%29%2A%28n+%2B+1%29+=+0+
+n+=+11+
+n+=+-1+
n can be either -1 or 11
check:
+136+=+%285+-+n%29%5E2+%2B+10%5E2+
+136+=+%285+-+%28-1%29%29%5E2+%2B+10%5E2+
+136+=+6%5E2+%2B+10%5E2+
+136+=+136+
OK
+136+=+%285+-+11%29%5E2+%2B+10%5E2+
+136+=+%28-6%29%5E2+%2B+10%5E2+
+136+=+36+%2B+100+
+136+=+136+
OK