document.write( "Question 982217: How do I solve the quadratic equation 36x squared minus 25=0? I tried using the quadratic formula and factoring, but can't get an answer that's right. \n" ); document.write( "
Algebra.Com's Answer #603070 by macston(5194)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "Difference of two squares:
\n" ); document.write( "\"36x%5E2-25=0\"
\n" ); document.write( "Take square root of 1st term plus square root of 2nd term:
\n" ); document.write( "6x+5
\n" ); document.write( "Multiply by square root of 1st term minus square root of 2nd term:
\n" ); document.write( "\"%286x%2B5%29%286x-5%29=0\"
\n" ); document.write( "\"6x%2B5=0\" \"or\" \"6x-5=0\"
\n" ); document.write( "\"6x=-5\" \"or\" \"6x=5\"
\n" ); document.write( "\"x=-%285%2F6%29\" \"or\" \"6=5%2F6\"
\n" ); document.write( "x=plus or minus (0.8333)
\n" ); document.write( ".
\n" ); document.write( "However, the quadratic formula does work:
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "\n" ); document.write( "
Solved by pluggable solver: SOLVE quadratic equation with variable
Quadratic equation \"ax%5E2%2Bbx%2Bc=0\" (in our case \"36x%5E2%2B0x%2B-25+=+0\") has the following solutons:
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\n" ); document.write( " \"x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca\"
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\n" ); document.write( " For these solutions to exist, the discriminant \"b%5E2-4ac\" should not be a negative number.
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\n" ); document.write( " First, we need to compute the discriminant \"b%5E2-4ac\": \"b%5E2-4ac=%280%29%5E2-4%2A36%2A-25=3600\".
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\n" ); document.write( " Discriminant d=3600 is greater than zero. That means that there are two solutions: \"+x%5B12%5D+=+%28-0%2B-sqrt%28+3600+%29%29%2F2%5Ca\".
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\n" ); document.write( " \"x%5B1%5D+=+%28-%280%29%2Bsqrt%28+3600+%29%29%2F2%5C36+=+0.833333333333333\"
\n" ); document.write( " \"x%5B2%5D+=+%28-%280%29-sqrt%28+3600+%29%29%2F2%5C36+=+-0.833333333333333\"
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\n" ); document.write( " Quadratic expression \"36x%5E2%2B0x%2B-25\" can be factored:
\n" ); document.write( " \"36x%5E2%2B0x%2B-25+=+36%28x-0.833333333333333%29%2A%28x--0.833333333333333%29\"
\n" ); document.write( " Again, the answer is: 0.833333333333333, -0.833333333333333.\n" ); document.write( "Here's your graph:
\n" ); document.write( "\"graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+36%2Ax%5E2%2B0%2Ax%2B-25+%29\"
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