Q107 of 160 Page 144

State whether the statements are true (T) or false (F).
If opposite angles of a quadrilateral are equal, it must be parallelogram.

TRUE

Let ABCD be a parallelogram, with A = α and B = β.

We have to Prove that C = α and D = β.

α + β = 180° (co-interior angles, AD || BC),

C = α (co-interior angles, AB || DC)

D = β (co-interior angles, AB || DC).

105

State whether the statements are true (T) or false (F).

Rectangle is a regular quadrilateral.

106

State whether the statements are true (T) or false (F).

If diagonals of a quadrilateral are equal, it must be a rectangle.

108

The interior angles of the triangle are in the ratio 1:2:3, then the ratio of its exterior angles is 3:2:1.

109

State whether the statements are true (T) or false (F).

is a concave pentagon.

State whether the statements are true (T) or false (F).If opposite angles of a quadrilateral are equal, it must be parallelogram.