Yes, I agree with the researcher's method. All the values of
in the table correspond to the values of n by using their formula.
Step-by-step explanation:
Step 1:
If we substitute the values of n in the researcher's equation and we get the right values of
, we can agree with the researcher's method.
The researcher's formula is
Here
is the wombat population and n is the number of years.
Step 2:
When n = 1, 
when n = 2, 
when n = 3, 
when n = 4, 
when n = 5, 
As all the values correspond to the values on the table, I agree with the researcher's method.
Your answer would be y= 5x/-4 - 3/-4 because you’ll move 5x to the other side of the equal sign then divide -4 to get y by itself
Given:
64 total students
x = drama club students
y = yearbook club students
x = y + 10
y = 64 - x
y = 64 - x
y = 64 - (y + 10)
y = 64 - y - 10
y + y = 64 - 10
2y = 54
2y/2 = 54/2
y = 27
x = y + 10
x = 27 + 10
x = 37
To check:
x + y = 64
37 + 27 = 64
64 = 64

Hope you could get an idea from here.
Doubt clarification - use comment section.