Answer:
8 y = -x + 1
9 y = x - 1
11 y = x + 2
12 y = -x - 3
Explanation:
for 8 and 9 just subtract the x and move it to the other side
for 11 and 12 do the same thing move x to the other side but since y is negative you flip all of the signs on both sides of the equation