document.write( "Question 281596: Factor as completely as possible.
\n" ); document.write( "a) \"x%5E3-4x\"
\n" ); document.write( "b) \"xy-x%2B8y-8\"
\n" ); document.write( "c) \"x%5E3%2Bx%5E2-90x\"\r
\n" ); document.write( "\n" ); document.write( "Hello! You dont have to do all three of these (unless you want too; go ahead and knock yourself out ;) ) What I wanted to know was if someone could please explain to me how I would factor these as completely as possible?
\n" ); document.write( "Thank you
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Algebra.Com's Answer #204571 by Mathematicians(84)\"\" \"About 
You can put this solution on YOUR website!
I'll knock myself out ;)\r
\n" ); document.write( "\n" ); document.write( "a) \"x%5E3-4x\"
\n" ); document.write( "b) \"xy-x%2B8y-8\"
\n" ); document.write( "c) \"x%5E3%2Bx%5E2-90x\"\r
\n" ); document.write( "\n" ); document.write( "a) We first want to look for any greatest common factors, notice there is an x in each term which is our greatest common factor!\r
\n" ); document.write( "\n" ); document.write( "\"x%5E3+-+4x+=+x%28x%5E2+-+4%29\" Notice how an x comes out of both terms
\n" ); document.write( "\"x%28x%5E2+-+4%29+=+x%28x%2B2%29%28x-2%29\" this is binomial factoring, we can do this because there is a minus sign in between \"x%5E2\" and \"4\". also, both \"4\" and \"x%5E2\" can be square rooted perfectly.\r
\n" ); document.write( "\n" ); document.write( "So the final answer is:\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28x%28x%2B2%29%28x-2%29%29\"\r
\n" ); document.write( "\n" ); document.write( "b) This example is a super use of greatest common factoring, sometimes noted as gcd:\r
\n" ); document.write( "\n" ); document.write( "\"xy-x%2B8y-8\" group the first two together and the last two:\r
\n" ); document.write( "\n" ); document.write( "\"%28xy+-+x%29+%2B+%288y+-+8%29\" then factor by greatest common factoring:
\n" ); document.write( "\"x%28y-1%29+%2B+8%28y+-+1%29\" we can see that there are two y-1, we can factor that out too:
\n" ); document.write( "\"%28y-1%29+%28x+%2B+8%29\" the easiest way to see this step is to take out the y-1 and whatever is left over is your second term.
\n" ); document.write( "\"highlight%28%28y-1%29+%28x+%2B+8%29%29\" is your final answer\r
\n" ); document.write( "\n" ); document.write( "c) \"x%5E3%2Bx%5E2-90x\"\r
\n" ); document.write( "\n" ); document.write( "Once again start off with greatest common factoring, there is an x is each of those:\r
\n" ); document.write( "\n" ); document.write( "\"x%28x%5E2+%2B+x+-+90%29\"
\n" ); document.write( "Now we want to find two things that multiply to be negative 90 and add up to be positive 1. One number is going to have to be a negative because that is the only way to multiply two numbers to get -90. The answer for this one is -9 and +10 which reduces to our final factoring:\r
\n" ); document.write( "\n" ); document.write( "\"highlight%28x+%28x+%2B+10%29+%28x+-+9%29%29\" final answer
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