document.write( "Question 78008: x^2+5x-14 divided by x^3+10x+21X\r
\n" ); document.write( "\n" ); document.write( "Hi, I just wante to make sure I have the right answers, which is X-2 over x(X+3). Thank You!
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Algebra.Com's Answer #55910 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
Does your problem look like this?\r
\n" ); document.write( "\n" ); document.write( "\"%28x%5E2%2B5x-14%29%2F%28x%5E2%2B10x%2B21%29\"\r
\n" ); document.write( "\n" ); document.write( "If this is the case, I'm afraid you don't have the answer (despite what the other tutor said. He must have quickly glanced at it).\r
\n" ); document.write( "\n" ); document.write( "First factor the numerator\r
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Solved by pluggable solver: Factoring Quadratics with a leading coefficient of 1 (a=1)
In order to factor \"1%2Ax%5E2%2B5%2Ax%2B-14\", first we need to ask ourselves: What two numbers multiply to -14 and add to 5? Lets find out by listing all of the possible factors of -14
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\n" ); document.write( " Factors:
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\n" ); document.write( " 1,2,7,14,
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\n" ); document.write( " -1,-2,-7,-14,List the negative factors as well. This will allow us to find all possible combinations
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\n" ); document.write( " These factors pair up to multiply to -14.
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\n" ); document.write( " (-1)*(14)=-14
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\n" ); document.write( " (-2)*(7)=-14
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\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
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First Number|Second Number|Sum
1|-14|1+(-14)=-13
2|-7|2+(-7)=-5
-1|14|(-1)+14=13
-2|7|(-2)+7=5
We can see from the table that -2 and 7 add to 5.So the two numbers that multiply to -14 and add to 5 are: -2 and 7\r\n" ); document.write( " \r\n" ); document.write( " Now we substitute these numbers into a and b of the general equation of a product of linear factors which is:\r\n" ); document.write( " \r\n" ); document.write( " \"%28x%2Ba%29%28x%2Bb%29\"substitute a=-2 and b=7\r\n" ); document.write( " \r\n" ); document.write( " So the equation becomes:\r\n" ); document.write( " \r\n" ); document.write( " (x-2)(x+7)\r\n" ); document.write( " \r\n" ); document.write( " Notice that if we foil (x-2)(x+7) we get the quadratic \"1%2Ax%5E2%2B5%2Ax%2B-14\" again\n" ); document.write( "

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\n" ); document.write( "\n" ); document.write( "Factor the denominator\r
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Solved by pluggable solver: Factoring Quadratics with a leading coefficient of 1 (a=1)
In order to factor \"1%2Ax%5E2%2B10%2Ax%2B21\", first we need to ask ourselves: What two numbers multiply to 21 and add to 10? Lets find out by listing all of the possible factors of 21
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\n" ); document.write( " Factors:
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\n" ); document.write( " 1,3,7,21,
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\n" ); document.write( " -1,-3,-7,-21,List the negative factors as well. This will allow us to find all possible combinations
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\n" ); document.write( " These factors pair up to multiply to 21.
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\n" ); document.write( " 1*21=21
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\n" ); document.write( " 3*7=21
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\n" ); document.write( " (-1)*(-21)=21
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\n" ); document.write( " (-3)*(-7)=21
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\n" ); document.write( " note: remember two negative numbers multiplied together make a positive number
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\n" ); document.write( " Now which of these pairs add to 10? Lets make a table of all of the pairs of factors we multiplied and see which two numbers add to 10
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First Number|Second Number|Sum
1|21|1+21=22
3|7|3+7=10
-1|-21|-1+(-21)=-22
-3|-7|-3+(-7)=-10
We can see from the table that 3 and 7 add to 10. So the two numbers that multiply to 21 and add to 10 are: 3 and 7\r\n" ); document.write( " \r\n" ); document.write( " Now we substitute these numbers into a and b of the general equation of a product of linear factors which is:\r\n" ); document.write( " \r\n" ); document.write( " \"%28x%2Ba%29%28x%2Bb%29\"substitute a=3 and b=7\r\n" ); document.write( " \r\n" ); document.write( " So the equation becomes:\r\n" ); document.write( " \r\n" ); document.write( " (x+3)(x+7)\r\n" ); document.write( " \r\n" ); document.write( " \r\n" ); document.write( " Notice that if we foil (x+3)(x+7) we get the quadratic \"1%2Ax%5E2%2B10%2Ax%2B21\" again\n" ); document.write( "

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\n" ); document.write( "\n" ); document.write( "So when we factor the numerator and denominator we get:\r
\n" ); document.write( "\n" ); document.write( "\"%28%28x-2%29%28x%2B7%29%29%2F%28%28x%2B3%29%28x%2B7%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"%28%28x-2%29cross%28%28x%2B7%29%29%29%2F%28%28x%2B3%29cross%28%28x%2B7%29%29%29\" Cancel like terms\r
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\n" ); document.write( "\n" ); document.write( "\"%28x-2%29%2F%28x%2B3%29\" So this is your answer. \r
\n" ); document.write( "\n" ); document.write( "In other words, \"%28x%5E2%2B5x-14%29%2F%28x%5E2%2B10x%2B21%29\" reduces to \"%28x-2%29%2F%28x%2B3%29\"\r
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\n" ); document.write( "\n" ); document.write( "note: you were close though. You just had an extra x in your denominator.\r
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\n" ); document.write( "\n" ); document.write( "Notice if you graph \"%28x%5E2%2B5x-14%29%2F%28x%5E2%2B10x%2B21%29\" you get\r
\n" ); document.write( "\n" ); document.write( " graph of \"%28x%5E2%2B5x-14%29%2F%28x%5E2%2B10x%2B21%29\"\r
\n" ); document.write( "\n" ); document.write( "it should be the same as the graph of \"%28x-2%29%2F%28x%2B3%29\"\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+%28x-2%29%2F%28x%2B3%29%29+\" graph of \"%28x-2%29%2F%28x%2B3%29\"\r
\n" ); document.write( "\n" ); document.write( "We can see that they are equal. So this verifies our answer. \n" ); document.write( "
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