Answer:
y = (x^2 + 6) / 2
Step-by-step explanation:
Original function: 
To find the inverse of a function we have to switch the x and y values and solve for y again
x = sqrt (2y-6)
To get rid of a square root we square the square root so:
x^2 = 2y-6
Add 6
x^2 + 6 = 2y
Divide by 2
y = (x^2 + 6) / 2
Since, population of species A is represented by : 
Let us find the population of species A, at the end of week 1:
i.e., x = 1
i.e., 
i.e., 
i.e., 
Also, since population of species B is represented by : 
Let us find the population of species B, at the end of week 1:
i.e., x = 1
i.e., 
i.e., 
i.e., 
Thus, at the end of 1 week, species A and species B will have the same population.
Hence, option D is correct.
I'm guessing the repeating part is 89 at the end, so that

Then





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An arguably quicker way without using geometric series:




Answer: 1,120 frogs
Step-by-step explanation:
If 12 out of every 180 frogs in the population have spots on their backs, the number that do not are;
= 180 - 12
= 168 frogs
168 frogs out of every 180 do not have spots. Out of 1,200 that would be;
= 168/180 * 1,200
= 1,120 frogs