A rectangle of length x, where x varies, has a constant area of 48cm2. Express the perimeter, y in terms of x. Find the least possible value of x. my problem is not the maths part i.e. the differentiation, but the equation to get things moving. I really have no idea where to start. I drew a rectangle, but am not sure if I am suppose to call the width by a letter. What's really confusing me is the "x varies", what dose this mean? All I see I have an x and a 48 which to me, I cant seem to connect with the perimeter. I would really appreciate some guidance here if possible. Thanks in advance.