First we use the quation given to solve for y.
-2y + 6 = 2 ------> Subtract 6 from both sides. (-6+2=-4)
-2y = - 4 ------> Divide both sides by -2 (-4/-2=2)
y = 2
Now you substitute the value of y or 2 into the first expression.
9(2)-9----> Multiply
18-9------->Subtract
9