It is given in the question that
Kelly bought a new car for $20,000. The car depreciates at a rate of 10% per year.
And we have to find the decay factor.
In equation
[tex]y = a(b)^x[/tex]
b is the decay factor which is equal to
[tex]b=1-r[/tex]
Where r is the rate .
And in the given question, r is 10 % , that is 0.1.
So decay factor is
[tex]b = 1-r = 1-0.1=0.9[/tex]
So the decay factor is 0.9 .
