Question 725322


{{{6x^2+18x-600}}} Start with the given expression.



{{{6(x^2+3x-100)}}} Factor out the GCF {{{6}}}.



Now let's try to factor the inner expression {{{x^2+3x-100}}}



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Looking at the expression {{{x^2+3x-100}}}, we can see that the first coefficient is {{{1}}}, the second coefficient is {{{3}}}, and the last term is {{{-100}}}.



Now multiply the first coefficient {{{1}}} by the last term {{{-100}}} to get {{{(1)(-100)=-100}}}.



Now the question is: what two whole numbers multiply to {{{-100}}} (the previous product) <font size=4><b>and</b></font> add to the second coefficient {{{3}}}?



To find these two numbers, we need to list <font size=4><b>all</b></font> of the factors of {{{-100}}} (the previous product).



Factors of {{{-100}}}:

1,2,4,5,10,20,25,50,100

-1,-2,-4,-5,-10,-20,-25,-50,-100



Note: list the negative of each factor. This will allow us to find all possible combinations.



These factors pair up and multiply to {{{-100}}}.

1*(-100) = -100
2*(-50) = -100
4*(-25) = -100
5*(-20) = -100
10*(-10) = -100
(-1)*(100) = -100
(-2)*(50) = -100
(-4)*(25) = -100
(-5)*(20) = -100
(-10)*(10) = -100


Now let's add up each pair of factors to see if one pair adds to the middle coefficient {{{3}}}:



<table border="1"><th>First Number</th><th>Second Number</th><th>Sum</th><tr><td  align="center"><font color=black>1</font></td><td  align="center"><font color=black>-100</font></td><td  align="center"><font color=black>1+(-100)=-99</font></td></tr><tr><td  align="center"><font color=black>2</font></td><td  align="center"><font color=black>-50</font></td><td  align="center"><font color=black>2+(-50)=-48</font></td></tr><tr><td  align="center"><font color=black>4</font></td><td  align="center"><font color=black>-25</font></td><td  align="center"><font color=black>4+(-25)=-21</font></td></tr><tr><td  align="center"><font color=black>5</font></td><td  align="center"><font color=black>-20</font></td><td  align="center"><font color=black>5+(-20)=-15</font></td></tr><tr><td  align="center"><font color=black>10</font></td><td  align="center"><font color=black>-10</font></td><td  align="center"><font color=black>10+(-10)=0</font></td></tr><tr><td  align="center"><font color=black>-1</font></td><td  align="center"><font color=black>100</font></td><td  align="center"><font color=black>-1+100=99</font></td></tr><tr><td  align="center"><font color=black>-2</font></td><td  align="center"><font color=black>50</font></td><td  align="center"><font color=black>-2+50=48</font></td></tr><tr><td  align="center"><font color=black>-4</font></td><td  align="center"><font color=black>25</font></td><td  align="center"><font color=black>-4+25=21</font></td></tr><tr><td  align="center"><font color=black>-5</font></td><td  align="center"><font color=black>20</font></td><td  align="center"><font color=black>-5+20=15</font></td></tr><tr><td  align="center"><font color=black>-10</font></td><td  align="center"><font color=black>10</font></td><td  align="center"><font color=black>-10+10=0</font></td></tr></table>



From the table, we can see that there are no pairs of numbers which add to {{{3}}}. So {{{x^2+3x-100}}} cannot be factored.



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<a name="ans">


Answer:



So {{{6x^2+18x-600}}} simply factors to {{{6(x^2+3x-100)}}}



In other words, {{{6x^2+18x-600=6(x^2+3x-100)}}}.