Thanks for responding in a grown-up way Taco.
You do not know what x is straight away you have to find it.
You know that 48+x farms grow potatoes (that is an expression in terms of x)
You know that 12+x farms grow beets
and
You know that 3 times more farms grow potatoes then beets.
so
48+x=3(12+x)
Now you have to solve this
48+x=36+3x
minus x from both sides
48=36+2x
subtract 36 from both sides
12=2x
divide both sides by 2
x=6
check
potato farmers 48+6=54
beet farmers 12+6=18
18*3=54 that is great.
so x=6
So how many farms have been included so far? Add them up.
There are 100 farms altogether so you can find the number of farms that do not grow either one.