The perimeter of a rectangular field is 246 yards. if the width of the field is 56 yards, what is its length?

Remember the formula for the perimeter of a rectangle is (2L + 2W).
Since we have our width, 56, we need to double it.
56 x 2 = 112.
Now we are left with this equation:
246 = 112 + 2L

To solve for this, we need to get 2L by itself and simplify.
Subtract 112 from both sides (what you do to one side of an equation you must do to the other).
246 - 112 = 134
112 - 112 = 0

Our equation is now:

2L = 134
L is being multiplied by 2.
To solve for L, we need to perform the opposite order of equations.
The opposite of multiplying is dividing.
Divide both sides by 2.

2L / 2 = L
134 / 2 = 67

You are left with:
L = 67

Your length is 67 yards.
I hope this helps!