From the sum of 3x – y + 11 and – y – 11, subtract 3x – y – 11.

Dear Student

First we have to find out the sum of 3x–y + 11 and–y–11
= 3x–y + 11 + (-y - 11)
= 3x–y + 11–y–11
= 3x–y–y + 11–11
= 3x–2y
Now, subtract 3x–y–11 from 3x–2y
= 3x–2y–(3x–y - 11)
= 3x–2y–3x + y + 11
= 3x–3x–2y + y + 11
= -y + 11

​Thanks