I believe yo meant c=2pir but ok
c=2r
divide both sides by 2
c/2=r
if you forgot tthe pi
c=2pir
divide by 2pi
c/(2pi)=r
It should be 3.5 if im correct
The polynomial is: 
Step-by-step explanation:
We need to write a polynomial f(x) that meets the given conditions: Degree 3 polynomial with zeros 3,-5,4
Since zeros are at 3,-5 and 4
So, x=3, x=-5 and x=4
or:
x-3=0, x+5=0 and x-4=0
Multiplying all factors to find the polynomial:

So, the polynomial is: 
keywords: Factors and zeros of polynomial
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