Question

The difference of nine and a number is eleven

Answer 1

Let the unknown number be x,

According to question,

9-x= 11
or
x-9=11

So
x=9-11
or
x=11+9

So,

x=-3
or
x=20..

Hope it helps ^_^

Answer 2

let the no. be x
x-9=11
x=11+9
x=20.
I hope you wanna the same answer as you hadn't mentioned in the question above....