Steps of Construction:
1. Draw a line segment BC=8 cm
2. Draw a perpendicular bisector PQ of BC dividing BC at point M.
3. From QP cut off a distance MA=4 cm
4. Join AC and AB
5. Draw an arc below BC, making an acute angle, angle CBX.
6. Along BX, mark off 3 points
B1,B2,B3 such that BB1=B1B2=B2B3
7. Join B2C
8. Join B3C′ which is parallel to B2C and join A′C′ which is parallel to AC
Thus, ΔA′BC′ is required triangle.