document.write( "Question 151501: For about what value(s) of x does g(x)=k(x) if g(x)=2x^2 -8 and k(x) =-x^2 -2?\r
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Algebra.Com's Answer #111358 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given equations.\r
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\n" ); document.write( "\n" ); document.write( "\"g%28x%29=2x%5E2+-8\" and \"k%28x%29+=-x%5E2+-2\"\r
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\n" ); document.write( "\n" ); document.write( "Since \"g%28x%29=k%28x%29\", this means that \"2x%5E2+-8=-x%5E2+-2\"\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-8=-x%5E2-2\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"2x%5E2-8%2B1x%5E2%2B2=0\" Add \"x%5E2\" to both sides. Add 2 to both sides.\r
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\n" ); document.write( "\n" ); document.write( "\"3x%5E2-6=0\" Combine like terms.\r
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\n" ); document.write( "\n" ); document.write( "Notice we have a quadratic equation in the form of \"ax%5E2%2Bbx%2Bc\" where \"a=3\", \"b=0\", and \"c=-6\"\r
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\n" ); document.write( "\n" ); document.write( "Let's use the quadratic formula to solve for x\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-b+%2B-+sqrt%28+b%5E2-4ac+%29%29%2F%282a%29\" Start with the quadratic formula\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-%280%29+%2B-+sqrt%28+%280%29%5E2-4%283%29%28-6%29+%29%29%2F%282%283%29%29\" Plug in \"a=3\", \"b=0\", and \"c=-6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+0-4%283%29%28-6%29+%29%29%2F%282%283%29%29\" Square \"0\" to get \"0\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+0--72+%29%29%2F%282%283%29%29\" Multiply \"4%283%29%28-6%29\" to get \"-72\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+0%2B72+%29%29%2F%282%283%29%29\" Rewrite \"sqrt%280--72%29\" as \"sqrt%280%2B72%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+72+%29%29%2F%282%283%29%29\" Add \"0\" to \"72\" to get \"72\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+sqrt%28+72+%29%29%2F%286%29\" Multiply \"2\" and \"3\" to get \"6\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0+%2B-+6%2Asqrt%282%29%29%2F%286%29\" Simplify the square root (note: If you need help with simplifying square roots, check out this solver) \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-0%29%2F%286%29+%2B-+%286%2Asqrt%282%29%29%2F%286%29\" Break up the fraction. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+0+%2B-+sqrt%282%29\" Reduce. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+sqrt%282%29\" or \"x+=+-sqrt%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+sqrt%282%29\" or \"x+=+-sqrt%282%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=1.414\" or \"x=-1.414\"
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