SOLUTION: s2-2s=5

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Question 443026: s2-2s=5
Answer by swincher4391(1107) About Me  (Show Source):
You can put this solution on YOUR website!
s%5E2+-2s+=+5
Solve for 0.
s%5E2+-+2s+-5+=+0
Factor if possible:
What adds up to -2 and multiples to -5?
Unfortunately 5 is prime, so 1 and 5 are the only factors.
Let's complete the square.
s%5E2+-2s+=5
To complete the square, we must take %28b%2F2%29%5E2 and make that the c term.
%28-2%2F2%29%5E2+=+1
s%5E2+-+2s+%2B+1++=+5+%2B+1+ we must add 1 to keep the equation balanced.
%28s-1%29%5E2+=+6
sqrt%28s-1%29%5E2+=+sqrt%286%29
s-1+=+0%2B-+sqrt%286%29
s+=+1%2B-+sqrt%286%29