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 #153934 by jsmallt9(3758)\"\" \"About 
You can put this solution on YOUR website!
this is where it gets confusing:
\n" ); document.write( "\"%288+%2B-+sqrt%28124%29%29%2F10\"
\n" ); document.write( "The next step is simplifying the square root. Simplifying square roots is done by finding perfect square factors of the radicand (the number inside the square root), if possible. The largest perfect square factor in 124 is 4. So we can rewrite 124 as 4*31:
\n" ); document.write( "\"%288+%2B-+sqrt%284%2A31%29%29%2F10\"
\n" ); document.write( "Then we can use a property of square roots, \"sqrt%28a%2Ab%29+=+sqrt%28a%29%2Asqrt%28b%29\", to split apart the two factors:
\n" ); document.write( "\"%288+%2B-+sqrt%284%29%2Asqrt%2831%29%29%2F10\"
\n" ); document.write( "Now we can simplify square root of the perfect square:
\n" ); document.write( "\"%288+%2B-+2%2Asqrt%2831%29%29%2F10\"
\n" ); document.write( "The only thing left to do is reduce the fraction. This is done, as always, by finding common factors which will cancel. In this case 2 is a factor of both the numerator and denominator. So if we factor it out we can cancel them:
\n" ); document.write( "\"%282%284+%2B-+sqrt%2831%29%29%29%2F%282%2A5%29\"
\n" ); document.write( "Now the 2's cancel leaving:
\n" ); document.write( "\"%284+%2B-+sqrt%2831%29%29%2F5\"
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