document.write( "Question 118752: Please help with this problem 3x^2 + x -4 = 0 What is the solution set ?\r
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Algebra.Com's Answer #86881 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 \"3%2Ax%5E2%2Bx-4=0\" ( notice \"a=3\", \"b=1\", and \"c=-4\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+%281%29%5E2-4%2A3%2A-4+%29%29%2F%282%2A3%29\" Plug in a=3, b=1, and c=-4\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+1-4%2A3%2A-4+%29%29%2F%282%2A3%29\" Square 1 to get 1 \r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+1%2B48+%29%29%2F%282%2A3%29\" Multiply \"-4%2A-4%2A3\" to get \"48\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+sqrt%28+49+%29%29%2F%282%2A3%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28-1+%2B-+7%29%2F%282%2A3%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+=+%28-1+%2B-+7%29%2F6\" Multiply 2 and 3 to get 6\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+=+%28-1+%2B+7%29%2F6\" or \"x+=+%28-1+-+7%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "Lets look at the first part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-1+%2B+7%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=6%2F6\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=1\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=1\"\r
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\n" ); document.write( "\n" ); document.write( "Now lets look at the second part:\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28-1+-+7%29%2F6\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-8%2F6\" Subtract the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=-4%2F3\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=-4%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=1\" or \"x=-4%2F3\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"3%2Ax%5E2%2Bx-4\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-14%2C+11%2C+-14%2C+11%2C3%2Ax%5E2%2B1%2Ax%2B-4%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=1\" and \"x=-4%2F3\". This verifies our answer\r
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