SOLUTION: P(3,1) and Q(-1,a) are 5 units apart. Find a.

Algebra ->  Length-and-distance -> SOLUTION: P(3,1) and Q(-1,a) are 5 units apart. Find a.      Log On


   

Question 385818: P(3,1) and Q(-1,a) are 5 units apart. Find a.
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
We have

5+=+sqrt%28%283+-+%28-1%29%29%5E2+%2B+%281-a%29%5E2%29
5+=+sqrt%2816+%2B+%281-a%29%5E2%29
%281-a%29%5E2+=+9
1-a+=+3 or 1-a+=+-3

a = -2 or 4