2 times a number subtracted by x
The phrase a number means an arbitrary variable, let's call it n.
n
2 times a number means we multiply n by 2:
2n
The phrase subtracted by means we subtract 2n from x:
x - 2n
The phrase a number means an arbitrary variable, let's call it n.
n
2 times a number means we multiply n by 2:
2n
The phrase subtracted by means we subtract 2n from x:
x - 2n