Question: Luke has blue and red balls.
Every day, he wins 2 blue balls and loses 3 red ones
After 5 days, he has the same amount of blue and re
After 9 days, he has twice as many blue balls as rec
How many red balls did he have at the beginning?

The number of red balls, in the beginning, is 47.

Step-by-step explanation:

According to the question,

Should let the number of blue balls will be "x" in the beginning and indeed the number of red balls will be "y".

After five days,

⇒   ...(equation 1)

After nine days,

⇒   ...(equation 2)

On applying subtraction between the above two equations, we get

⇒  

⇒  

whole numbers.

step-by-step explanation:

we are given the average monthly rainfall (in millimeters) model r(m) for the years 1900-2009 as a function of the month number m.

as we can see m is taken for the number of months for years 1900-2009.

we know that number of months can't be a negative number or decimal number or a fraction.

so, the number of months could be only positive whole numbers.

therefore, whole numbers is more appropriate for the domain of r.