The four unknown pieces of rope are said to be an equal length, so each piece will be represented by x. Now there is another 10 feet of rope that is attached, and that all together equals 30 feet. The equation is:
4x + 10 = 30
4x = 20
x = 5
(I'm so sorry I can't draw a diagram for you, but I hope you will be able to using the equation shown above!)
