Question 64336
When you are dividing by x+5 you start the process with -5.
because you are testing the root x=-5 and you are finding
f(-5) which in your problem turns out to be zero, indicating
that -5 is a root and x=5 is a factor of your 4th degree 
polynomial.
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I have put in the intermediate step in the synthetic 
division process.  Does that help you understand 
how I arrived at the Quotient and Remainder?
Cheers,
Stan H.
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3x^4+11x^3-20x^2+7x+35/x+5 
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-5)...3....11....-20....7....35
 
..........-15.....+20....0...-35
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......3....-4.......0.....7..|..0

Quotient: 3x^3-4x^2+7
Remainder: 0