Question

1. A quadrilateral with one pair of opposite sides parallel is called a $\_\_\_\_\_$

2. The diagonals of a rhombus bisect each and other at $\_\_\_\_\_$

3. When any two triangles are said to be congruent?

4. The angles of the triangles are ${\left(x-35\right)}^o{\left(x-20\right)}^o$ and ${\left(x+40\right)}^o$ find the three angles.

5. Which is smaller: the perimeter of a square or the perimeter of a circle inscribed in it ?

Answer 1

$\left(1\right)$A quadrilateral with one pair of opposite sides parallel is called a trapezium

$\left(2\right)$ The diagonals of a rhombus bisect each and other at ${90}^o$

$\left(3\right)$ two triangles are said to be congruent if their corresponding sides and angles are equal.
$\left(4\right)$ the angles of the triangles are $(x-35{)}^o$, $(x-20{)}^o$, $(x+40{)}^o$

$\therefore (x-35)+(x-20)+(x+40)={180}^o$

$x={65}^o$

$\therefore$ the angles are ${30}^o$ , ${45}^o$ , ${105}^o$

$\left(5\right)$The perimeter of circle.