Make a straight line AB then construct an angle of 120 degrees at point B. Cut off an arc equal to 10 cm on the straight line produced from the 120 degree line. You now have created line BC.
Once you have an intersection point, using a compass, draw an arc with the compass stretched up to 8 cm from the point C. Similarly, draw an arc with the compass stretched up to 10 cm from point A, the first point you drew.
Once you have intersecting arcs, connect the intersections and you've constructed a parallelogram.
For this construction, we use the property of parallelograms that opposite sides are equal in their length.
Construct on a single diagram parallelogram ABCD with AB=8cm,BC=10cm and ABC=120 degrees
2 answers
Very good solution for this question.