Hey there! 
11 = 12 - q
-q + 12 = 11
SUBTRACT 12 to BOTH SIDES 
-q + 12 - 12 = 11 - 12
SIMPLIFY IT! 
-q = 11 - 12 
-q = -1
-1q = -1
DIVIDE -1 to BOTH SIDES 
-1q/-1 = -1/-1 
SIMPLIFY IT!
q = -1/-1
q = 1
Therefore, your answer should be: 
q = 1
Good luck on your assignment & enjoy your day!
~Amphitrite1040:)