SOLUTION: Using the quadratic formula to solve x2 + 20 = 2x, what are the values of x?

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Question 948127: Using the quadratic formula to solve x2 + 20 = 2x, what are the values of x?
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

x%5E2+%2B+20+=+2x ...first write it in ax%5E2%2Bbx%2Bc=0 form
x%5E2-2x+%2B+20+=+0
x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+ ..in your case a=1, b=-2, and c=20

x+=+%28-%28-2%29+%2B-+sqrt%28+%28-2%29%5E2-4%2A1%2A20+%29%29%2F%282%2A1%29+
x+=+%282+%2B-+sqrt%28+4-80+%29%29%2F2+
x+=+%282+%2B-+sqrt%28+-4%2A19+%29%29%2F2+
x+=+%282+%2B-+2sqrt%2819+%29%2Ai%29%2F2+
x+=+%28cross%282%291+%2B-+cross%282%291sqrt%2819+%29%2Ai%29%2Fcross%282%291+
x+=+%281+%2B-+sqrt%2819+%29%2Ai%29+
so, we have complex solutions which means there is no x-intercepts:
x+=+1+%2B+sqrt%2819+%29%2Ai+
x+=+1+-+sqrt%2819+%29%2Ai+

+graph%28+600%2C+600%2C+-10%2C+10%2C+-10%2C+55%2C+x%5E2-2x+%2B+20+%29+