Answer:
The exponential growth function is 
Step-by-step explanation:
Given: The population of a certain city was 145,380 in 2000 and 219,135 in 2010.
To find: exponential growth function that models the growth of the city
Solution:
The exponential growth function is given by 
Here, P denotes total population after time t
denotes initial population
k denotes rate of growth
t denotes time
As
,

As 

Answer:
3 hours
Step-by-step explanation:
We can solve using ratios
18 lbs 12 lbs
------------ = --------------
4.5 hrs x hours
Using cross products
18x = 12 * 4.5
18x = 54
Divide by 18
18x/18 = 54/18
x=3
Y=2x
so what you do is sub 2x for y in the top equation
x^2+(2x)^2=5
x^2+4x^2=5
5x^2=5
divide both sides by 5
x^2=1
sqrt both sides
x=1 or -1
sub back
y=2x
y=2(-1)
y=-2
y=2(1)
y=2
the solutions are (1,2) and (-1,-2)
If you multiply 38*(-36) you would get -1368. And to convert that into a fraction it could be -1368/1, -13680/10, etc.