The correct option is A l=26 m,w=20 m
Let l and w be the length and width of the room, respectively.
Then, the perimeter of the room will be 2(l+w) m.
Based on the given information,
l=6+w......(1)
12×2(l+w)=46
⇒l+w=46......(2)
Let's solve these two equations using the substitution method.
Substituting the value of l from equation (1) in equation (2), we get
⇒6+w+w=46
⇒6+2w=46
⇒2w=46−6
⇒2w=40
⇒w=402
⇒w=20 m
l=20+6=26 m
Therefore, the length and width are 26 m and 20 m, respectively.