SOLUTION: If ax^3 + 2x^2 + 5 is exactly divisible by x+1,what is the value of a? Thanks

Question 1033979: If ax^3 + 2x^2 + 5 is exactly divisible by x+1,what is the value of a?
Thanks
Found 2 solutions by Theo, stanbon:
Answer by Theo(13342) (Show Source): You can put this solution on YOUR website!
i believe it will be 7.

i used synthetic division to figure it out.

my worksheet is shown here.
look below the worksheet for more comments.

if you need a tutorial on how to do synthetic divison, look here.
http://www.mesacc.edu/~scotz47781/mat120/notes/divide_poly/synthetic/synthetic_division.html
i set it up for synthetic division with the coefficient of the leading term as a.
i then went through the process and wound up with 5 + (2-a) as the last result.
this last result is the remainder.
i then set it to 0 and solved for a to get a = 7.
i then testing that out to see if i wind up with a remainder of 0, which i did.
that's your solution.
a = 7.

Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
If ax^3 + 2x^2 + 5 is exactly divisible by x+1,what is the value of a?
----
Use synthetic division::
-1)....a....2....0....5
.......a...2-a..a-2..|..7-a
------
Solve:
7-a = 0
a = 7
---------------
Cheers,
Stan H.
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