Answer:
=12y+18
Step-by-step explanation:
=(3)(6+4y)
=(3)(6)+(3)(4y)
=18+12y
=12y+18
It's the third one because if you look at the other ones
Width = X
Length = X + 15
Perimeter of a Rectangle = 2W + 2L
2(X) + 2(X + 15)
2X + 2X + 30
4X + 30
Answer = 4X + 30
Hope this helps! :)