Think of a triangle having each side equal.

Try to find out by marking right angles inside the square.

Measure of angle of straight line

Try to recall the things which you learnt about triangle.

Think about the angles of rectangle

Try to recall the properties of square.

Think about the polygon with 4 sides

Think of name of line segment between opposite vertices of rectangle

Try to recall the things which you learnt about triangle.

Try to remember the properties of rectangle.