Answer :
ok so find greatert common factor
ab+ac=a(b+c)
15x=3*5*x
9=3*3
gcf=3
15x-9=
3(5x)+3(-3)=
3(5x-3)
possible dimentions is 3 unit and 5x-3 units
ab+ac=a(b+c)
15x=3*5*x
9=3*3
gcf=3
15x-9=
3(5x)+3(-3)=
3(5x-3)
possible dimentions is 3 unit and 5x-3 units