document.write( "Question 148119: Factor: (2x^(2/3)) - (5x^(1/3)) - 3 \n" ); document.write( "
Algebra.Com's Answer #108504 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Start with the given expression.\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Let . This means that \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " Replace with . Replace with \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Looking at \"2z%5E2-5z-3\" we can see that the first term is \"2z%5E2\" and the last term is \"-3\" where the coefficients are 2 and -3 respectively.\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now multiply the first coefficient 2 and the last coefficient -3 to get -6. Now what two numbers multiply to -6 and add to the middle coefficient -5? Let's list all of the factors of -6:\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Factors of -6:\r
\n" ); document.write( "\n" ); document.write( "1,2,3,6\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "-1,-2,-3,-6 ...List the negative factors as well. This will allow us to find all possible combinations\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "These factors pair up and multiply to -6\r
\n" ); document.write( "\n" ); document.write( "(1)*(-6)\r
\n" ); document.write( "\n" ); document.write( "(2)*(-3)\r
\n" ); document.write( "\n" ); document.write( "(-1)*(6)\r
\n" ); document.write( "\n" ); document.write( "(-2)*(3)\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "note: remember, the product of a negative and a positive number is a negative number\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now which of these pairs add to -5? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to -5\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\n" ); document.write( "\n" ); document.write( "
First NumberSecond NumberSum
1-61+(-6)=-5
2-32+(-3)=-1
-16-1+6=5
-23-2+3=1
\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "From this list we can see that 1 and -6 add up to -5 and multiply to -6\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now looking at the expression \"2z%5E2-5z-3\", replace \"-5z\" with \"1z%2B-6z\" (notice \"1z%2B-6z\" adds up to \"-5z\". So it is equivalent to \"-5z\")\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"2z%5E2%2Bhighlight%281z%2B-6z%29%2B-3\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now let's factor \"2z%5E2%2Bz-6z-3\" by grouping:\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"%282z%5E2%2Bz%29%2B%28-6z-3%29\" Group like terms\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"z%282z%2B1%29-3%282z%2B1%29\" Factor out the GCF of \"z\" out of the first group. Factor out the GCF of \"-3\" out of the second group\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"%28z-3%29%282z%2B1%29\" Since we have a common term of \"2z%2B1\", we can combine like terms\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So \"2z%5E2-5z-3\" factors to \"%28z-3%29%282z%2B1%29\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( " Now replace \"z\" with \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "So factors to \r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "In other words, where every variable is positive.
\n" ); document.write( "
\n" );