posted by puk .
3. An elastic string hangs from a nail N. When as mass of m grams is attached to its lower end, the elastic is stretched so that its lower length is x cm, as shown in the diagram:
N The table shows result of the two experiments:
Length (x cm) 43 49
Mass (m grams) 50 80
It is known that x and m are connected by the equation x = c + dm, where c and d are constants.
(a) Solve your equations to find the value of c and the value of d.
(b) Find the mass at the end of the string when its length is 40 cm.
(c) What does the value of c represents?