document.write( "Question 370439: How do u factor this trinomial 10a^2-9a+2 ?
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document.write( "Ex. 3x^2+10x+8
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document.write( " (4)(2)=8
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document.write( " (3x+4)(x+2)
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document.write( " (3x)(2)=6x
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document.write( " (4)(x)=4x
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document.write( " 6x+4x=10x \n" );
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Algebra.Com's Answer #264210 by jsmallt9(3758)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( "With the 10 and 2 being positive and with the -9 in the middle, we can tell that the factors, if any, will both have minus signs, After all, we want products that are positive but a sum that is negative. So our factors will be of the form: \n" ); document.write( "( - )( - ) \n" ); document.write( "(If you don't see this, then it will just take you longer to factor because you will be trying \n" ); document.write( "( + )( + ) \n" ); document.write( "( - )( + ) \n" ); document.write( "( + )( - ) \n" ); document.write( "with no hope of any of these working.) \n" ); document.write( "For the 10 in front we know that the factors are either 5 and 2 or 10 and 1. For the two in the back the only factors are 1 and 2. So the possibilities are: \n" ); document.write( "(5a - 2)(2a - 1) \n" ); document.write( "(5a - 1)(2a - 2) \n" ); document.write( "(10a - 2)(a - 1) \n" ); document.write( "(10a - 1)(a - 2) \n" ); document.write( "The middle two: \n" ); document.write( "(5a - 1)(2a - 2) \n" ); document.write( "(10a - 2)(a - 1) \n" ); document.write( "can't work because one of the factors has a common factor. Since \n" ); document.write( "(5a - 2)(2a - 1) \n" ); document.write( "(10a - 1)(a - 2) \n" ); document.write( "If you multiply these out, you will find that the first one works. So \n" ); document.write( " |