document.write( "Question 220696: I need help with a quadratic Equation 2x^2=90
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Algebra.Com's Answer #165616 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"2x%5E2=90\" Start with the given equation\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-90=0\" Subtract 90 from both sides\r
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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 \"2%2Ax%5E2-90=0\" (note: since the polynomial does not have an \"x\" term, the 2nd coefficient is zero. In other words, b=0. So that means the polynomial really looks like \"2%2Ax%5E2%2B0%2Ax-90=0\" notice \"a=2\", \"b=0\", and \"c=-90\")
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\n" ); document.write( " \"x+=+%280+%2B-+sqrt%28+%280%29%5E2-4%2A2%2A-90+%29%29%2F%282%2A2%29\" Plug in a=2, b=0, and c=-90
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\n" ); document.write( " \"x+=+%280+%2B-+sqrt%28+0-4%2A2%2A-90+%29%29%2F%282%2A2%29\" Square 0 to get 0
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\n" ); document.write( " \"x+=+%280+%2B-+sqrt%28+0%2B720+%29%29%2F%282%2A2%29\" Multiply \"-4%2A-90%2A2\" to get \"720\"
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\n" ); document.write( " \"x+=+%280+%2B-+sqrt%28+720+%29%29%2F%282%2A2%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%280+%2B-+12%2Asqrt%285%29%29%2F%282%2A2%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+=+%280+%2B-+12%2Asqrt%285%29%29%2F4\" Multiply 2 and 2 to get 4
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\n" ); document.write( " So now the expression breaks down into two parts
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\n" ); document.write( " \"x+=+%280+%2B+12%2Asqrt%285%29%29%2F4\" or \"x+=+%280+-+12%2Asqrt%285%29%29%2F4\"
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\n" ); document.write( " Now break up the fraction
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\n" ); document.write( " \"x=0%2F4%2B12%2Asqrt%285%29%2F4\" or \"x=0%2F4-12%2Asqrt%285%29%2F4\"
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\n" ); document.write( " Simplify
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\n" ); document.write( " \"x=0%2B3%2Asqrt%285%29\" or \"x=0-3%2Asqrt%285%29\"
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\n" ); document.write( " So the solutions are:
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\n" ); document.write( " \"x=0%2B3%2Asqrt%285%29\" or \"x=0-3%2Asqrt%285%29\"
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