QUADRILATERALS

In a quadrilateral, ABCD, angleDAB + angleBCD=180^(@) , then the quadrilateral ABCD is……………….

The midpoints of the sides AB,BC,CD and DA of a quadrilateral ABCD are joined to form a quadrilateral.If AC=BD and AC perp BD then prove that the quadrilateral formed is a square.

The quadrilateral formed by joining the midpoints of the sides of a quadrilateral ABCD, taken in order, is a rhombus, if

The quadrilateral formed by joining the midpoints of the sides of a quadrilateral ABCD, taken in order, is a rectangle, if

The given figure shows a quadrilateral ABCD. What is the area of quadrilateral ABCD?

ABCD is a cyclic quadrilateral (see Figure). Find the angles of the cyclic quadrilateral.

In the quadrilateral ABCD:

Given the following statements : A:If the diagonals of a quadrilateral bisect each other, then the quadrilateral is a parallelogram. B: If the diagonals of a quadrilateral do not bisect each other, then the quadrilateral is not a parallelogram. Identify these as contrapositive or converse of each other.

If the diagonals AC,BD of a quadrilateral ABCD, intersect at O, and separate the quadrilateral into four triangles of equal area, show that quadrilateral ABCD is a parallelogram.

The sum of the four angles of a quadrilateral is 360^(@) . In a quadrilateral ABCD, the angles A, B, C and D are in the ratio 1:2: 4:5, then the measure of each angle of a quadrilateral is