1. Draw a line segment BC = 6 cm.
2. With B as a center and radius 2.5 cm, draw an arc.
3. With C as a center and radius 6.5 cm, draw another arc, cutting the previous arc at A.
4. Join AB and AC.
Then, ?ABC is the required triangle.
5. When we will measure the angle B of triangle by protractor, then angle is equal to ?B = 90°