document.write( "Question 843273: Find all solutions of the equation x^2+1x+7=0 and express them in the form a+bi \n" ); document.write( "
Algebra.Com's Answer #508056 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: Quadratic Formula
Let's use the quadratic formula to solve for x:

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\n" ); document.write( " Starting with the general quadratic
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\n" ); document.write( " \"ax%5E2%2Bbx%2Bc=0\"
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\n" ); document.write( " the general solution using the quadratic equation is:
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\n" ); document.write( " \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"
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\n" ); document.write( " So lets solve \"x%5E2%2Bx%2B7=0\" ( notice \"a=1\", \"b=1\", and \"c=7\")
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\n" ); document.write( " \"x+=+%28-1+%2B-+sqrt%28+%281%29%5E2-4%2A1%2A7+%29%29%2F%282%2A1%29\" Plug in a=1, b=1, and c=7
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\n" ); document.write( " \"x+=+%28-1+%2B-+sqrt%28+1-4%2A1%2A7+%29%29%2F%282%2A1%29\" Square 1 to get 1
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\n" ); document.write( " \"x+=+%28-1+%2B-+sqrt%28+1%2B-28+%29%29%2F%282%2A1%29\" Multiply \"-4%2A7%2A1\" to get \"-28\"
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\n" ); document.write( " \"x+=+%28-1+%2B-+sqrt%28+-27+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%28-1+%2B-+3%2Ai%2Asqrt%283%29%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
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\n" ); document.write( " \"x+=+%28-1+%2B-+3%2Ai%2Asqrt%283%29%29%2F%282%29\" Multiply 2 and 1 to get 2
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\n" ); document.write( " After simplifying, the quadratic has roots of
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\n" ); document.write( " \"x=-1%2F2%2B3%2Asqrt%283%29%2F2%2Ai\" or \"x=-1%2F2-3%2Asqrt%283%29%2F2%2Ai\"
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\n" ); document.write( "\n" ); document.write( "note: those solutions are of the form \"a%2Bbi\". In the first case, \"a+=+-1%2F2\", \"b+=+3%2Asqrt%283%29%2F2\"
\n" ); document.write( "In the second case, \"a+=+-1%2F2\", \"b+=+-3%2Asqrt%283%29%2F2\"
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