document.write( "Question 67554: x^2-2x-15=0 by factoring, find the roots of the equation \n" ); document.write( "
Algebra.Com's Answer #48127 by checkley71(8403)\"\" \"About 
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x^2-2x-15=0 Because the x^2 factor is =1 you need to find two numbers that satisfy the following criteria. n1*n2=-15 & n1+n2=-2.
\n" ); document.write( "First find all factors of -15 & they are:
\n" ); document.write( "-1&15
\n" ); document.write( "1&-15
\n" ); document.write( "-3&5
\n" ); document.write( "3&-5
\n" ); document.write( "now choose the set that when added =-2
\n" ); document.write( "-1+15=14 not an answer
\n" ); document.write( "1-15=-14 not an answer
\n" ); document.write( "-3+5=2 not an answer
\n" ); document.write( "3-5=-2 ANSWER! Now add thes two answers to the x term thus:
\n" ); document.write( "(x-5)(x+3)=0 Then set each term=0 (because for two numbers multiplied together &=0, one of them must be=0) and solve thus:
\n" ); document.write( "x-5=0
\n" ); document.write( "x=5 solution
\n" ); document.write( "x+3=0
\n" ); document.write( "x=-3 solution
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\n" ); document.write( "Hope this helps :) \n" ); document.write( "
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