Question 6 (a)
From the sum of 3x - y + 11 and - y - 11, subtract 3x – y – 11.
According to question,
= (3x - y + 11) + (- y - 11) - (3x - y - 11)
= 3x - y + 11 - y - 11 - 3x + y + 11
= 3x - 3x - y - y + y + 11 - 11 + 11
= (3 - 3)x - (1 + 1 - 1)y + 11 + 11 -11
= 0x - y + 11
= - y +11
The required expression is -y + 11.