B and C can be divided by 9.
Answer:
The shaded area is 
Step-by-step explanation:
we know that
The shaded area is equal to the area of the large square minus the area of the two smaller squares
so

Calculate the shaded area
Remember that

substitute

Can you ummm finish the question
Answer:
9a - 2b
Step-by-step explanation:
6a - 6b +3a +4b . . . . . . . we assume your _ is supposed to be -
= a(6 +3) +b(-6 +4)
= 9a -2b