document.write( "Question 96856: x^2-48=0 \n" ); document.write( "
Algebra.Com's Answer #70477 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Let's use the quadratic formula to solve for x:\r
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\n" ); document.write( "\n" ); document.write( "Starting with the general quadratic\r
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\n" ); document.write( "\n" ); document.write( "\"ax%5E2%2Bbx%2Bc=0\"\r
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\n" ); document.write( "\n" ); document.write( "the general solution using the quadratic equation is:\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"\r
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\n" ); document.write( "\n" ); document.write( "So lets solve \"x%5E2-48=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 \"x%5E2%2B0%2Ax-48=0\" notice \"a=1\", \"b=0\", and \"c=-48\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+sqrt%28+%280%29%5E2-4%2A1%2A-48+%29%29%2F%282%2A1%29\" Plug in a=1, b=0, and c=-48\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+sqrt%28+0-4%2A1%2A-48+%29%29%2F%282%2A1%29\" Square 0 to get 0 \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+sqrt%28+0%2B192+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-48%2A1\" to get \"192\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+sqrt%28+192+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+8%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)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+8%2Asqrt%283%29%29%2F2\" Multiply 2 and 1 to get 2\r
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\n" ); document.write( "\n" ); document.write( "So now the expression breaks down into two parts\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B+8%2Asqrt%283%29%29%2F2\" or \"x+=+%280+-+8%2Asqrt%283%29%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "Now break up the fraction\r
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\n" ); document.write( "\n" ); document.write( "\"x=0%2F2%2B8%2Asqrt%283%29%2F2\" or \"x=0%2F2-8%2Asqrt%283%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=4%2Asqrt%283%29\" or \"x=-4%2Asqrt%283%29\"\r
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\n" ); document.write( "\n" ); document.write( "So these expressions approximate to\r
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\n" ); document.write( "\n" ); document.write( "\"x=6.92820323027551\" or \"x=-6.92820323027551\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=6.92820323027551\" or \"x=-6.92820323027551\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"x%5E2-48\", we get:\r
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\n" ); document.write( "\n" ); document.write( "when we use the root finder feature on a calculator, we find that \"x=6.92820323027551\" and \"x=-6.92820323027551\".So this verifies our answer
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