Answer:

Step-by-step explanation:
Given
The attached graph
Required

This is the point where

On the attached graph;
when 
Hence:

Answer:
C. 10 000
Step-by-step explanation:
If we called:
x = children who have been vacinated against rubella only
2x = children who have been vaccinated against mumps
y = children who have been vaccinated agains both
Children who have been vaccinated against mumps only = x - y
And we know that y = 2*(x-y)
=> 2y = 3x
y = 5000
There fore x = 7500
The number of children who have been vaccinated against rubella
= 2x - y = 2*7500 - 5000 = 15 000 - 5000 = 10 000
To write it in function notation you'll convert it into a function, substituting y by f(x):
y = 3x - 8 = f(x) = 3x - 8
Hope it helped,
BioTeacher101
3-83= 80
80 divided by 2 is 40
the answer is 40