Steps of construction:
Step 1: Draw a line segment BC of 3.5cm.
Step 2: At B, draw an angle XBC of 45o
Step 3: With center B and radius 1.5cm, draw an arc which intersects BX at D.
Step 4: Join DC
Step 5: Draw the perpendicular bisector of DC which intersects BD produced at A.
Step 6: Join AC
Therefore Δ ABC is the required triangle