Question 31738
An equilateral triangle with sides 8 feet each makes the perimeter of the triangle 8*3 = 24 feet;
Perimeter of rectangle is 2(length+width) = perimeter of the traingle
=> 15 + 2*width = 24 
=> 2*width = 9
=> width = 4.5
Answer: width of the rectangle is 4.5 feet