Part A: the area of a rectangle is A= lw, so
A= lw
Height= 6x+3.= 9x
Width= 8
Which makes the expression to this area 9x x 8 ( 9x times 8 )
Part B: you do the same to get the expression here, so the expression would be
6x x 12 ( 6x times 12 )
The answer to this part is yes because both end up being 72x once you get the answer of each.