Answer:
R = 6
Step-by-step explanation:
Given the equation of the line is 2x - Ry = 30
We know that the equation of a line with a as x-intercept and b as y-intercept is 
Now convert the above given line to the standard form
Divide the line by 30 we get


Here the y-intercept is 30/R
Given y-intercept = 5

R = 6
15 2/6 or 15 1/3 (simplest form) because 3x6+5=23/6 x 4/1 = 92/6 converted to mixed number is 15 1/3
Knowing the amount doubles every 30 days, we'll have to find how many times it'lll double in the 210-day time frame:
210 / 30 = 7
It doubles 7 times. If we were to write a rough, not worked on expresion representing that, knowing the starting population was of 20, we would write:
(((((((20 * 2) * 2) * 2) * 2) * 2) * 2) * 2) = 2560 rabbits
Hope it helped,
Happy homework/ study exam!