SOLUTION: express x squared -8x+20=0 in simplest a+bi form

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Question 826709: express x squared -8x+20=0 in simplest a+bi form
Answer by jsmallt9(3758) About Me  (Show Source):
You can put this solution on YOUR website!
x%5E2-8x%2B20=0
This does not factor. So we move on to the Quadratic Formula:
x+=+%28-%28-8%29%2B-sqrt%28%28-8%29%5E2-4%281%29%2820%29%29%29%2F2%281%29
Simplifying...
x+=+%28-%28-8%29%2B-sqrt%2864-4%281%29%2820%29%29%29%2F2%281%29
x+=+%28-%28-8%29%2B-sqrt%2864-80%29%29%2F2%281%29
x+=+%28-%28-8%29%2B-sqrt%28-16%29%29%2F2%281%29
x+=+%288%2B-sqrt%28-16%29%29%2F2
x+=+%288%2B-sqrt%28-1%2A16%29%29%2F2
x+=+%288%2B-sqrt%28-1%29%2Asqrt%2816%29%29%2F2
x+=+%288%2B-+i%2A4%29%2F2
x+=+%288%2B-+4i%29%2F2
x+=+%282%284%2B-+2i%29%29%2F2
x+=+%28cross%282%29%284%2B-+2i%29%29%2Fcross%282%29
x+=+4%2B-+2i
which is short for:
x+=+4%2B+2i or x+=+4-+2i
The first solution is already in a + bi form. The second needs to be rewritten as an addition:
x+=+4%2B+2i or x+=+4+%2B+%28-2%29i