document.write( "Question 152870: For about what value(s) of x does g(x) = k(x) if g(x) = x^3 + 2x^2 and k(x) = x^3 – x^2 + 6?
\n" ); document.write( "a. x = ± 2.3
\n" ); document.write( "b. x ≈ 2.3
\n" ); document.write( "c. x ≈ ± 1.4
\n" ); document.write( "d. x ≈ 1.4
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Algebra.Com's Answer #112351 by jim_thompson5910(35256)\"\" \"About 
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\"g%28x%29+=+k%28x%29+\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "\"x%5E3+%2B+2x%5E2=+x%5E3+-+x%5E2+%2B+6\" Plug in \"g%28x%29+=+x%5E3+%2B+2x%5E2\" and \"k%28x%29+=+x%5E3+-+x%5E2+%2B+6\"\r
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\n" ); document.write( "\n" ); document.write( "\"0=++-+3x%5E2+%2B+6\" Subtract \"x%5E3\" from both sides. Subtract \"2x%5E2\" from both sides.\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%28-3%29%286%29+%29%29%2F%282%28-3%29%29\" Plug in \"a=-3\", \"b=0\", and \"c=6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+sqrt%28+0-4%28-3%29%286%29+%29%29%2F%282%28-3%29%29\" Square \"0\" to get \"0\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+sqrt%28+0--72+%29%29%2F%282%28-3%29%29\" Multiply \"4%28-3%29%286%29\" to get \"-72\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+sqrt%28+0%2B72+%29%29%2F%282%28-3%29%29\" Rewrite \"sqrt%280--72%29\" as \"sqrt%280%2B72%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+sqrt%28+72+%29%29%2F%282%28-3%29%29\" Add \"0\" to \"72\" to get \"72\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+sqrt%28+72+%29%29%2F%28-6%29\" Multiply \"2\" and \"-3\" to get \"-6\". \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%280+%2B-+6%2Asqrt%282%29%29%2F%28-6%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+=+%280%29%2F%28-6%29+%2B-+%286%2Asqrt%282%29%29%2F%28-6%29\" Break up the fraction. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+0+%2B-+-1%2Asqrt%282%29\" Reduce. \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+0-1%2Asqrt%282%29\" or \"x+=+0%2B1%2Asqrt%282%29\" Break up the expression. \r
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\n" ); document.write( "\n" ); document.write( "So the answers are \"x+=+0-1%2Asqrt%282%29\" or \"x+=+0%2B1%2Asqrt%282%29\" \r
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\n" ); document.write( "\n" ); document.write( "which approximate to \"x=-1.414\" or \"x=1.414\" \r
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\n" ); document.write( "\n" ); document.write( "So the answer choice is c) x ≈ ± 1.4
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