Question

Construct an isosceles triangle whose base is 4.8 cm and whose vertical angle is 80°.

Answer 1

Steps of construction:
1. Draw a line segment BC = 4.8 cm.
2. Construct $\angle$CBX = 80$°$.
4. Make $\angle$XBY = 90$°$.
5. Draw the right bisector PQ of BC intersecting BY at O.
6. With O as the centre and radius OB, draw a arc intersecting PQ at A.
7. Join AC and AB.
Thus, ABC is the required triangle.