document.write( "Question 204020: I need help with one part of solution when using the quadratic formula. My textbook does not explain this part. I will list up to where I begin to get confused.\r
\n" ); document.write( "\n" ); document.write( "Solve: 5x^2-8x-3=0\r
\n" ); document.write( "\n" ); document.write( "a=5, b=-8. c=-3\r
\n" ); document.write( "\n" ); document.write( "-(-8)+/- sqrt(-8)^2-4(5)(-3) divided by 2(5)\r
\n" ); document.write( "\n" ); document.write( "8 +/- sqrt64+60 divided by 10\r
\n" ); document.write( "\n" ); document.write( "8 +/- sqrt124 divided by 10\r
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\n" ); document.write( "\n" ); document.write( "this is where it gets confusing:
\n" ); document.write( "8+/- sqrt (4) (31) divided by 10\r
\n" ); document.write( "\n" ); document.write( "8+/- 2 sqrt31 divided by 10 =2(4+/- sqrt31 divided by (2)(5)\r
\n" ); document.write( "\n" ); document.write( "= 2/2 times 4+/- sqrt31 divided by 5 = 4+/-sqrt31 divided by 5\r
\n" ); document.write( "\n" ); document.write( "I do not understand what is happening during this part. Please walk me through and explain what is being done and why it is done. thank you
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Algebra.Com's Answer #153932 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
I'll start where you're starting to get confused\r
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\n" ); document.write( "\n" ); document.write( "\"x=%288%2B-sqrt%28124%29%29%2F%2810%29\" Start with the given equation.\r
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\n" ); document.write( "\n" ); document.write( "The goal now is to simplify the right side any way we can. It turns out that the square root can be simplified.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%288%2B-sqrt%284%2A31%29%29%2F%2810%29\" Factor 124 into 4*31. Note: 4*31=124. \r
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\n" ); document.write( "\n" ); document.write( "Why did we do this? Because when we break up the root, we can take the square root of 4 to get 2...\r
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\n" ); document.write( "\n" ); document.write( "\"x=%288%2B-sqrt%284%29%2Asqrt%2831%29%29%2F%2810%29\" Break up the square root.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%288+%2B-+2%2Asqrt%2831%29%29%2F%2810%29\" Take the square root of 4 to get 2.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%282%284%2B-sqrt%2831%29%29%29%2F%2810%29\" Factor out the GCF 2 from the numerator.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%282%284%2B-sqrt%2831%29%29%29%2F%282%2A5%29\" Factor the denominator 10 to get 2*5\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28highlight%282%29%284%2B-sqrt%2831%29%29%29%2F%28highlight%282%29%2A5%29\" Highlight the common terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%28cross%282%29%284%2B-sqrt%2831%29%29%29%2F%28cross%282%29%2A5%29\" Cancel out the common terms.\r
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\n" ); document.write( "\n" ); document.write( "\"x=%284%2B-sqrt%2831%29%29%2F5\" Simplify\r
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\n" ); document.write( "\n" ); document.write( "So the solutions are \"x=%284%2Bsqrt%2831%29%29%2F5\" or \"x=%284-sqrt%2831%29%29%2F5\" (since the 'plus/minus' breaks the equation in two).\r
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\n" ); document.write( "\n" ); document.write( "Note: I showed more steps than you would necessarily show to illustrate what is really going on.
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