SOLUTION: solve the quadratic equation 4x*2+16x+17=0 x=(-16(+-)4i)/2

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Question 518211: solve the quadratic equation 4x*2+16x+17=0
x=(-16(+-)4i)/2
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+4x%5E2+%2B+16x+%2B+17+=+0+
Divide both sides by +4+
+x%5E2+%2B+4x+%2B+17%2F4+=+0+
+x%5E2+%2B+4x+=+-17%2F4+
To complete the square, take 1/2
of the coefficient of x, square it,
and add it to both sides
+x%5E2+%2B+4x+%2B+%284%2F2%29%5E2+=+-17%2F4+%2B+%284%2F2%29%5E2+
+x%5E2+%2B+4x+%2B+4+=+-17%2F4+%2B+16%2F4+
+%28+x+%2B+2+%29%5E2+=+-1%2F4+
Take the square root of both sides
+x+%2B+2+=+i%2F2+
+x+=+%28+-4+%2B+i+%29%2F2+
and, also
+x+=+%28+-4+-+i+%29%2F2+
These answers seem to check out