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?
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}.
To find the length of the dog run space, we can use the formula for the perimeter of a rectangle, which is P = 2 * (length + width). Given that the total amount of fencing Sari has is 40 feet, and the width of the dog run space is 8 feet, we can substitute these values into the formula:
40 = 2 * (length + 8)
Now, let's solve for length. First, divide both sides of the equation by 2:
40/2 = length + 8
Simplifying this equation, we get:
20 = length + 8
To isolate the length on one side of the equation, subtract 8 from both sides:
20 - 8 = length
The length of the dog run space will be:
length = 12 feet
To find the length of the rectangular dog run, we can use the formula for the perimeter of a rectangle: P = 2L + 2W, where P is the perimeter, L is the length, and W is the width.
In this case, we know that the perimeter is 40 feet and the width is 8 feet. So we can set up the equation: 40 = 2L + 2(8).
To solve for L, we first simplify the equation: 40 = 2L + 16.
Next, we isolate L by subtracting 16 from both sides of the equation: 40 - 16 = 2L.
Simplifying further, we have: 24 = 2L.
To solve for L, we divide both sides of the equation by 2: 24 / 2 = L.
Therefore, the length of the rectangular dog run will be 12 feet.