document.write( "Question 92942: I am having problems with these problems\r
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\n" ); document.write( "\n" ); document.write( "x^2-x-2=0\r
\n" ); document.write( "\n" ); document.write( "and also 4x^2-3x+3=0\r
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Algebra.Com's Answer #67639 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\"Solve by using the quadratic formula
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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( "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-x-2=0\" ( notice \"a=1\", \"b=-1\", and \"c=-2\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--1+%2B-+sqrt%28+%28-1%29%5E2-4%2A1%2A-2+%29%29%2F%282%2A1%29\" Plug in a=1, b=-1, and c=-2\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+%28-1%29%5E2-4%2A1%2A-2+%29%29%2F%282%2A1%29\" Negate -1 to get 1\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+1-4%2A1%2A-2+%29%29%2F%282%2A1%29\" Square -1 to get 1 (note: remember when you square -1, you must square the negative as well. This is because \"%28-1%29%5E2=-1%2A-1=1\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+1%2B8+%29%29%2F%282%2A1%29\" Multiply \"-4%2A-2%2A1\" to get \"8\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%281+%2B-+sqrt%28+9+%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+=+%281+%2B-+3%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+=+%281+%2B-+3%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+=+%281+%2B+3%29%2F2\" or \"x+=+%281+-+3%29%2F2\"\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=%281+%2B+3%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=4%2F2\" Add the terms in the numerator\r
\n" ); document.write( "\n" ); document.write( "\"x=2\" Divide\r
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\n" ); document.write( "\n" ); document.write( "So one answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=2\"\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=%281+-+3%29%2F2\"\r
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\n" ); document.write( "\n" ); document.write( "\"x=-2%2F2\" Subtract 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 another answer is\r
\n" ); document.write( "\n" ); document.write( "\"x=-1\"\r
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\n" ); document.write( "\n" ); document.write( "So our solutions are:\r
\n" ); document.write( "\n" ); document.write( "\"x=2\" or \"x=-1\"\r
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\n" ); document.write( "\n" ); document.write( "Notice when we graph \"x%5E2-x-2\", we get:\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-11%2C+12%2C+-11%2C+12%2C1%2Ax%5E2%2B-1%2Ax%2B-2%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and we can see that the roots are \"x=2\" and \"x=-1\". This verifies our answer\r
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\n" ); document.write( "\n" ); document.write( "\"Solve by using the quadratic formula
\n" ); document.write( "4x^2-3x+3=0 \"\r
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\n" ); document.write( "
\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( "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 \"4%2Ax%5E2-3%2Ax%2B3=0\" ( notice \"a=4\", \"b=-3\", and \"c=3\")\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%28--3+%2B-+sqrt%28+%28-3%29%5E2-4%2A4%2A3+%29%29%2F%282%2A4%29\" Plug in a=4, b=-3, and c=3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+%28-3%29%5E2-4%2A4%2A3+%29%29%2F%282%2A4%29\" Negate -3 to get 3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9-4%2A4%2A3+%29%29%2F%282%2A4%29\" Square -3 to get 9 (note: remember when you square -3, you must square the negative as well. This is because \"%28-3%29%5E2=-3%2A-3=9\".)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+9%2B-48+%29%29%2F%282%2A4%29\" Multiply \"-4%2A3%2A4\" to get \"-48\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+sqrt%28+-39+%29%29%2F%282%2A4%29\" Combine like terms in the radicand (everything under the square root)\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+%283+%2B-+i%2Asqrt%2839%29%29%2F%282%2A4%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+=+%283+%2B-+i%2Asqrt%2839%29%29%2F%288%29\" Multiply 2 and 4 to get 8\r
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\n" ); document.write( "\n" ); document.write( "After simplifying, the quadratic has roots of\r
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\n" ); document.write( "\n" ); document.write( "\"x=3%2F8+%2B+sqrt%2839%29%2F8%2Ai\" or \"x=3%2F8+-+sqrt%2839%29%2F8%2Ai\"\r
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\n" ); document.write( "\n" ); document.write( "Notice if we graph the quadratic \"y=4%2Ax%5E2-3%2Ax%2B3\", we get\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-14.625%2C+15.375%2C+-12.5625%2C+17.4375%2C+4%2Ax%5E2-3%2Ax%2B3%29+\" graph of \"y=4%2Ax%5E2-3%2Ax%2B3\"\r
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\n" ); document.write( "\n" ); document.write( "And we can see that there are no real roots\r
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\n" ); document.write( "\n" ); document.write( "To visually verify the answer, check out this page to see a visual representation of imaginary roots
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