Sari is creating a dog run space in her backyard. She has 40 feet of fencing to go around the outside, and she wants to make it rectangular with a width of 8 feet. What will the length be, in feet?

Answer 1

Let's assume that the length of the dog run is L feet.
So the perimeter of the rectangle will be 2L+2W where W is the width of the rectangle.
We know that the perimeter is equal to the amount of fencing Sari has, so we can write 2L+2W=40.
Since the width is given as 8 feet, we can substitute this value into the equation as follows: 2L+2(8)=40.
Now we can simplify the equation: 2L+16=40.
Subtracting 16 from both sides of the equation gives: 2L=24.
Dividing both sides by 2 gives: L=<<12=12>>12.
So the length of the dog run will be 12 feet. Answer: \boxed{12}.