Answer:
the answer is -1
Step-by-step explanation:
Perimeter is the sum of all the sides. So we can set up an equation:

Now solve for 'x', combine like terms:
When it comes to terms with variables it's just like normal addition but we keep the variable:


So we have:

Add:

Subtract 7x to both sides:

Subtract 4 to both sides:

Divide 5 to both sides:
1 mile = 1760 yards
Therefore you must times 13 by 1760
13x1760 = 22880
A I believe please let me know