(9x)(11y)

(a)  

(9xy)(3)

(a)  

(-x)(-y)

(a)  

(0)(12xy)

(a)  

(2xy)(3)

(a)  

(-3x)(-6y) =

(a)  

(1x)(2y) =

(a)  

(2a)(3b)(4c) =

(a)  

(20a)(b)(c)

(a)