Answer:
12m
Explanation:
To find the area of the rectangle we multiply l by w
so
lw=a
if l=2+w we can substitute l with 2+w
so now
w(w+2)=168
distribute
w^2+2w=168
Now we use guess and check to solve
13^2 is 169
so 12^2 is 144 and 2*12=24
and 144+24=168