Answer:
width: 3.83
length: 3.66
Explanation:
The perimeter of a triangle is calculating by adding all the sides together (length + length + width + width). Since we are given the formula for the length we can simply substitute that formula and solve for the width which would be the only variable in the equation.
length + length + width + width = 15
(2w-4) + (2w-4) + w + w = 15 ... combine like terms
6w - 8 = 15 ... add 8 on both sides
6w = 15 ... divide both sides by 6
w = 3.83
Now that we know the value for the width we can plug it into the formula for the length to find its value
l = 2w - 4
l = 7.66 - 4
l = 3.66
Finally, we can see that the rectangle has a width of 3.83 and a length of 3.66