document.write( "Question 474270: x^2 - 13x + 36 \n" ); document.write( "
Algebra.Com's Answer #325288 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
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Solved by pluggable solver: Quadratic Formula
Let's use the quadratic formula to solve for x:

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\n" ); document.write( " Starting with the general quadratic
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\n" ); document.write( " \"ax%5E2%2Bbx%2Bc=0\"
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\n" ); document.write( " the general solution using the quadratic equation is:
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\n" ); document.write( " \"x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29\"
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\n" ); document.write( " So lets solve \"x%5E2-13%2Ax%2B36=0\" ( notice \"a=1\", \"b=-13\", and \"c=36\")
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\n" ); document.write( " \"x+=+%28--13+%2B-+sqrt%28+%28-13%29%5E2-4%2A1%2A36+%29%29%2F%282%2A1%29\" Plug in a=1, b=-13, and c=36
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\n" ); document.write( " \"x+=+%2813+%2B-+sqrt%28+%28-13%29%5E2-4%2A1%2A36+%29%29%2F%282%2A1%29\" Negate -13 to get 13
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\n" ); document.write( " \"x+=+%2813+%2B-+sqrt%28+169-4%2A1%2A36+%29%29%2F%282%2A1%29\" Square -13 to get 169 (note: remember when you square -13, you must square the negative as well. This is because \"%28-13%29%5E2=-13%2A-13=169\".)
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\n" ); document.write( " \"x+=+%2813+%2B-+sqrt%28+169%2B-144+%29%29%2F%282%2A1%29\" Multiply \"-4%2A36%2A1\" to get \"-144\"
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\n" ); document.write( " \"x+=+%2813+%2B-+sqrt%28+25+%29%29%2F%282%2A1%29\" Combine like terms in the radicand (everything under the square root)
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\n" ); document.write( " \"x+=+%2813+%2B-+5%29%2F%282%2A1%29\" Simplify the square root (note: If you need help with simplifying the square root, check out this solver)
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\n" ); document.write( " \"x+=+%2813+%2B-+5%29%2F2\" Multiply 2 and 1 to get 2
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\n" ); document.write( " So now the expression breaks down into two parts
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\n" ); document.write( " \"x+=+%2813+%2B+5%29%2F2\" or \"x+=+%2813+-+5%29%2F2\"
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\n" ); document.write( " Lets look at the first part:
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\n" ); document.write( " \"x=%2813+%2B+5%29%2F2\"
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\n" ); document.write( " \"x=18%2F2\" Add the terms in the numerator
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\n" ); document.write( " \"x=9\" Divide
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\n" ); document.write( " So one answer is
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\n" ); document.write( " \"x=9\"
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\n" ); document.write( " Now lets look at the second part:
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\n" ); document.write( " \"x=%2813+-+5%29%2F2\"
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\n" ); document.write( " \"x=8%2F2\" Subtract the terms in the numerator
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\n" ); document.write( " \"x=4\" Divide
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\n" ); document.write( " So another answer is
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\n" ); document.write( " \"x=4\"
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\n" ); document.write( " So our solutions are:
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\n" ); document.write( " \"x=9\" or \"x=4\"
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+500%2C+500%2C+-10%2C+30%2C+-10%2C+30%2C+x%5E2+-+13x+%2B+36%29+\"
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