Answer:
1. Perpendicular
2. Isosceles
3. Never
Step-by-step explanation:
1. AC ⊥ BD because diameter of a square are perpendicular bisector of each other.
2. In Δ AOB , By using pythagoras : AB² = OA² + OB² .......( 1 )
In Δ COB , By using pythagoras : BC² = OC² + OB² ..........( 2 )
But, OA = OC because both are radius of same circle
So, by using equations ( 1 ) and ( 2 ), We get AB = BC ≠ AC
⇒ ABC is a triangle having two equal sides so ABC is an isosceles triangle.
3. The side can never be equal to radius of circle because the side of the square will be chord for the circle and in a circle chord can never be equal to its radius
