group the 1st 2 terms and last 2 terms:
(Z63 -2z^2) + (9z-18)
factor out GCF:
z^2(z-2) + 9(z-2)
now factor the polynomial:
(z-2) (z^2+9)
Cos (314) = .694 is positive
Solution :
Transforming given equations :
From above equations we can see that equation 1) has largest percentage growth rate and the percent growth rate is 12% .
Hence, this is the required solution.