Question 179494
Do you want to factor? Please post full instructions.




Looking at the expression {{{2h^2-3h-18}}}, we can see that the first coefficient is {{{2}}}, the second coefficient is {{{-3}}}, and the last term is {{{-18}}}.



Now multiply the first coefficient {{{2}}} by the last term {{{-18}}} to get {{{(2)(-18)=-36}}}.



Now the question is: what two whole numbers multiply to {{{-36}}} (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 {{{-36}}} (the previous product).



Factors of {{{-36}}}:

1,2,3,4,6,9,12,18,36

-1,-2,-3,-4,-6,-9,-12,-18,-36



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



These factors pair up and multiply to {{{-36}}}.

1*(-36)
2*(-18)
3*(-12)
4*(-9)
6*(-6)
(-1)*(36)
(-2)*(18)
(-3)*(12)
(-4)*(9)
(-6)*(6)


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>-36</font></td><td  align="center"><font color=black>1+(-36)=-35</font></td></tr><tr><td  align="center"><font color=black>2</font></td><td  align="center"><font color=black>-18</font></td><td  align="center"><font color=black>2+(-18)=-16</font></td></tr><tr><td  align="center"><font color=black>3</font></td><td  align="center"><font color=black>-12</font></td><td  align="center"><font color=black>3+(-12)=-9</font></td></tr><tr><td  align="center"><font color=black>4</font></td><td  align="center"><font color=black>-9</font></td><td  align="center"><font color=black>4+(-9)=-5</font></td></tr><tr><td  align="center"><font color=black>6</font></td><td  align="center"><font color=black>-6</font></td><td  align="center"><font color=black>6+(-6)=0</font></td></tr><tr><td  align="center"><font color=black>-1</font></td><td  align="center"><font color=black>36</font></td><td  align="center"><font color=black>-1+36=35</font></td></tr><tr><td  align="center"><font color=black>-2</font></td><td  align="center"><font color=black>18</font></td><td  align="center"><font color=black>-2+18=16</font></td></tr><tr><td  align="center"><font color=black>-3</font></td><td  align="center"><font color=black>12</font></td><td  align="center"><font color=black>-3+12=9</font></td></tr><tr><td  align="center"><font color=black>-4</font></td><td  align="center"><font color=black>9</font></td><td  align="center"><font color=black>-4+9=5</font></td></tr><tr><td  align="center"><font color=black>-6</font></td><td  align="center"><font color=black>6</font></td><td  align="center"><font color=black>-6+6=0</font></td></tr></table>



From the table, we can see that there are no pairs of numbers which add to {{{-3}}}. So {{{2h^2-3h-18}}} cannot be factored.




So I would make sure that you entered the correct problem.