i really need help with this 6th grade work due today

5
Step-by-step explanation:
Length (L) = u
Breadth (b) = 6 mi
Perimeter (P) = 22 miles
Now we know
P = 2 (L+ b)
22 = 2 ( u + 6)
11 = u + 6
11 - 6 = u
u = 5
Answer:
u = 5
Step-by-step explanation:
The perimeter of a rectangle is all the sides added up.
The oppisite sides are parralel.
So the side across from 6 is all 6
6 + 6 = 12
The perimeter is 22 so you do
22 - 12 = 10
So 'u' equals 5 because you have to divide the number 10 by 2.