Answer:
23.
a)The object hits 150 feets after 9 seconds or 1 second
b)150 ft , time is 9 sec or 1 sec
24.
a) y=125000(0.8)^x
b)$40960
Explanation:
23.
Given the equation that models the height as
h=-16t²+160t+6 and h=150, re-write the equation as
150=-16t²+160t+6
150-6=-16t²+160t
144=-16t²+160t
16t²-160t+144=0------divide the terms by 16
t²-10t+9=0
factorize as
t²-t-9t+9=0
t(t-1)-9(t-1)=0
(t-9)(t-1)=0
t-9=0
t=9 or
(t-1)=0
t-1=0
t=1
The object hits 150 feets after 9 seconds or 1 second
b) maximum height is given as
h=-16t²+160t+6
h=-16(9²)+160*9+6
h= -1296 + 1440+6 = 150 ft
Time taken is 9 seconds or 1 second
24.
a)The formula for exponential decay is ;
y=a(1-b)^x
where
a=original amount
b=decay factor as a percentage
x=exponent, how often the decay occurs
Given that;
a=$125000
b=20% =0.2
Then
y=125000(1-0.2)^x
y=125000(0.8)^x --------is the exponential decay function
b)Given x=5
y= 125000(0.8)^5 =$40960