SOLUTION: Need help!! x² - 5x + 2 = 0

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Question 170532: Need help!!
x² - 5x + 2 = 0
Found 2 solutions by josmiceli, zandrad:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2+-+5x+%2B+2+=+0
Complete the square. It works like this:
Subtract 2 from both sides
x%5E2+-+5x+=+-2
Now take one-half of the co-efficient of x,
square it and add this to both sides.
x%5E2+-+5x+%2B+%28-5%2F2%29%5E2+=+-2+%2B+%28-5%2F2%29%5E2
x%5E2+-+5x+%2B+25%2F4+=+-2+%2B+25%2F4
The left side is a perfect square. Rewrite it.
%28x+-+5%2F2%29%5E2+=+-%288%2F4%29+%2B+25%2F4
%28x+-+5%2F2%29%5E2+=+17%2F4
Now take the square root of both sides
x+-+5%2F2+=+sqrt%2817%29+%2F+2
x+=+%285+%2B+sqrt%2817%29%29+%2F+2 answer 1
and, also, since square root is both (+) and (-)
x+=+%285+-+sqrt%2817%29%29+%2F+2 answer 2

Answer by zandrad(1) About Me  (Show Source):