Synthetic Division(NOT long division):
(x2 + 13x + 40) ÷ (x + 8)

Question

Synthetic Division(NOT long division):
(x2 + 13x + 40) ÷ (x + 8)

e.mccormick · Answer

What part of the process do you have trouble with?

anonymous · Answer

All of it... I just don't understand how to do it :/

e.mccormick · Answer

OK. Start with just the coefficients.  The division bar goes down rather than up in synthetic.  Have you seen that setup?

anonymous · Answer

I think so...

e.mccormick · Answer

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anonymous · Answer

Oh okayy!

e.mccormick · Answer

Now, for the coefficient of the divisor, you set it to $x=$ to find out what it is.  So for $x+8\implies x=-8$

e.mccormick · Answer

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e.mccormick · Answer

Now, the first number just gets carried down.  It is used no matter what it is.  This is why synthetic is only used in $x\pm n$ cases, and not used in  $ax\pm n$ cases.  If there was some value other than 1 with the x, this would not work.

e.mccormick · Answer

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amistre64 · Answer

i do a different setup, but same mechanics

e.mccormick · Answer

Next, you multiply what is doing the dividing by the number down there.  This gets you a number to do some math with to get the next number to work with.
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