SOLUTION: Given f(x)= -x^3 +7x^2 -9x -5 and that x = 5 is a root, find the other roots

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Question 758825: Given f(x)= -x^3 +7x^2 -9x -5 and that x = 5 is a root, find the other roots
Answer by josgarithmetic(39618) About Me  (Show Source):
You can put this solution on YOUR website!
Divide the function by x-5 to produce a quadratic quotient.

Through synthetic division:

5____|_____-1______7_____-9______-5
_____|
_____|___________-5______10______5
_____|_____-1______2_____1_______0

Note carefully the coefficients according to the bottom row:
-x%5E2%2B2x%2B1
Find the roots to this resulting polynomial using solution to quadratic formula.
%28-2%2B-+sqrt%284-4%28-1%29%281%29%29%29%2F%28-2%29
%28-2%2B-+sqrt%288%29%29%2F%28-2%29
%28-2%2B-+2%2Asqrt%282%29%29%2F%28-2%29
highlight%282%2B-+sqrt%282%29%29