b+b+b =

b.2.a.4 =

6a-4a =

x+x+y =

(3a).6 =

3a.4b =

a.(-5).7 =

2a-a =

(x+x).2 =

4a-3b =

f+f+f-f =

12.(a+a+a+a+a) =

2a+a+2b-b=

(-5).(-2).2a =

7x-10x =

-4.(-6b) =

7.(3a+4a) =

(-2).3b+7=

(2x+3x-5x).4 =

8.(2a+7a-4a) =