SOLUTION: Find the zeroes of x^3 - 16x^2 + 85x - 148

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Question 944822: Find the zeroes of x^3 - 16x^2 + 85x - 148
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
graph%28300%2C300%2C-2%2C8%2C-5%2C5%2Cx%5E3+-+16x%5E2+%2B+85x+-+148%29
Looks like highlight%28x=4%29 is a zero.
Verifying,
64-16%2A16%2B85%2A4-148=0
64-256%2B340-148=0
0=0
.
.
So then,
%28x%5E3+-+16x%5E2+%2B+85x+-+148%29%2F%28x-4%29=x%5E2-12x%2B37
So,
x%5E2-12x%2B37=0
x%5E2-12x%2B36%2B1=0
%28x-6%29%5E2=-1
x-6=0+%2B-+sqrt%28-1%29
highlight%28x=+6+%2B-+i%29