Graphical Method:

First draw the space diagram for the truss, and name the several members according to Bow's rotation.

Choose a convenient point a and draw ab = 1000 kg to a suitable scale. Now from b draw bd parallel to BD, and, from a draw ad parallel to AD meeting bd at d. Thus, abd is the vector diagram, for joint (1) - which point corresponds to joint A in Figure - where the relevant directions are a - b, b - d, and d - a.

Similarly draw the vector diagram adc for joint (2) whose relevant directions are, a - d, d - c, and c - a.

Measure the sides of the vector diagram, and listed the results, keeping in mind the force-scale selected by you.