Look at the given quadrilateral and answer the question: What are the sides of the given quadrilateral?

A polygon with four sides is called a quadrilateral. The line segments with which a quadrilateral is made up of are called the sides of the quadrilateral. The sides of the quadrilateral are A B , B C , C D and A D . Therefore, the sides of the quadrilateral A B C D are A B , B C , C D and A D .

Look at the given quadrilateral and answer the question: What is the opposite side of A B ?

The line segments with which a quadrilateral is made up of are called the sides of the quadrilateral. The side opposite of A B is C D . The side opposite of B C is A D . The side opposite of C D is A B . The side opposite of A D is B C . Therefore, the side opposite of A B is C D .

Look at the given quadrilateral and answer the question: What is the opposite vertex of B ?

The point where two sides of a quadrilateral meet is called a vertex of a quadrilateral. The vertex opposite of A is C . The vertex opposite of B is D . The vertex opposite of C is A . The vertex opposite of D is B . Therefore, the vertex opposite of B is D .

Look at the given quadrilateral and answer the question: What is the opposite angle of ∠ C ?

Two angles of a quadrilateral which are not adjacent angles are known as opposite angle. Here, ∠ B and ∠ C are adjacent angles. ∠ A is not an adjacent angle of ∠ C . Therefore, the opposite angle of ∠ C is ∠ A .

Look at the given quadrilateral and answer the question: How many pairs of adjacent angles are there? What are they?

Two angles of a quadrilateral are called adjacent angles, if they have a common side as an arm. ∠ A B C and ∠ B C D are adjacent angles. ∠ B C D and ∠ C D A are adjacent angles. ∠ C D A and ∠ D A B are adjacent angles. ∠ D A B and ∠ A B C are adjacent angles. Therefore, there are four pairs of adjacent angles.

Look at the given quadrilateral and answer the question: How many pairs of opposite angles are there? What are they?

Two angles of a quadrilateral which are not adjacent angles are known as opposite angles. Therefore, there are two pairs of opposite angles. The angle opposite of ∠ D A B is ∠ D C B . The angle opposite of ∠ A B C is ∠ A D C .