Let the triangle to be constructed be ΔABC.
Given:
BC=5.5 cm, ∠ABC=120∘ and ∠ACB=30∘
[1 mark]
Steps of construction:
Step I: Draw a line segment BC of length 5.5 cm using ruler.
[0.5 marks]
Step II: Draw an angle of 120∘ on point B and produce it to ray Y.
[0.5 marks]
Step III: Draw an angle of 30∘ on point C and produce it to ray X.
[0.5 marks]
Step IV: Extend −−→BY and −−→CX to intersect at point A.
[0.5 marks]
Hence, ΔABC is the required triangle with BC=5.5 cm, ∠ABC=120∘ and ∠ACB=30∘.
[2 marks]