Answer:
An exponential function has the form y = ab^x, where a and b are constants and x is the independent variable (in this case, time).
Given the initial condition that there were 4 bacteria in the dish, we know that when x = 0, y = 4.
So we can set up the equation: 4 = a(b^0)
Given the condition that 5 hours later there were 972 bacteria in the dish, we know that when x = 5, y = 972.
So we can set up the equation: 972 = ab^5
We can now solve for b by dividing the two equations:
972/4 = ab^5/a(b^0) = b^5
b = (972/4)^(1/5)
With b calculated, we can substitute it into one of the equations to find a:
4 = a(b^0) = ab^0 = a
So the exponential function that satisfies the given conditions is:
y = ab^x = 4(b^x) = 4( (972/4)^(1/5)^x)
This function models the growth of bacteria in the Petri dish