Answer:
50%
Step-by-step explanation:
This is essentially not a math question buth rather one of dietary reference and recommendeations. FAO gives the Estimated Average Requirement(EAR), as 0.5(50%). This figure is defined as the intake at which there's risk of inadequacy to an individual.
*View link below for more comprehensive information.
https://www.ncbi.nlm.nih.gov/books/NBK114332/
First find the x and y values because where the lines will intersect, they share the point of the intersection so they will share the x and y coordinates.
Rearrange equations


To cancel y, we must do equation 1 minus equation 2. Similarly:




So the x coordinate is 3.
The y coordinate can be found with substitution of x into one of the equations:

So where the two lines intersect is at the point (3, 7), which is the solution to the equations.
The factorized answer is 36!