The formula for the perimeter p of a rectangle with length l and width w is p=2•l+2•w a rectangle has length 100 meters. what is the perimeter if the width is 50 meters? what is the width if the perimeter is 344 meters?

1) What is the perimeter if the width is 50 meters? 
You are told that the formula for the perimeter is: P=2*l+2*w. You are also told that the length, l = 100m. To find the perimeter if the width, w = 50m, just plug the numbers into the formula and solve for P:
P=2*l+2*w
P=2(100) + 2(50)
P = 200 +100
P = 300m

2) What is the width if the perimeter is 344 meters?
Now you're told the perimeter, P = 344m, and asked to find the width. Use the same formula, P=2*l+2*w. The length is still l=100m:
P=2*l+2*w
344 = 2(100) + 2w
344 = 200 + 2w
144 = 2w
w = 72m



1) Perimeter = 300 meters
2) Width = 72 meters