Answer:
D. 13
Step-by-step explanation:
well since it's a quadratic equation, it can be written in the form of ax²+bx+c=0. So we have a=1, b=b and c= -30. Also the roots are given by the equation-
x= -b±
/2a. So all I did was put the number from the choices which would satisfy the sqrt part and that turned out to be 13 since
=
= 17. So b=13.
This is an equation of exponential decay
y(t) = a b^ t where a is the initial amount
b is the decay factor
t is the time in years
b is found by taking 1 and subtracting the percent it decreases in decimal form
Letting t =4
y(t) = 260 million * ( 1- .011) ^ 4
=248.7473796 million
=24874737.96
Rounding to a whole number
= 24874738