Question

12x^a y^b / (-6x^a y) ??

Answer 1

12 / ( - 6 ) = - 2 ;
x^a / x^a = 1 ;
y^b / y = y^( b - 1 ) ;
12x^a y^b / (-6x^a y) = ( - 2 ) x 1 x  y^( b - 1 ) = -2y^( b - 1 ) ;