The interior angles of a quadrilateral are 82°, (25x – 2) °, (20x – 1) ° and (25x + 1) °. Calculate the value of x.īy a property of quadrilaterals (Sum of interior angles = 360°), we have,Īnd the angles of the quadrilaterals are 70°, 80°, 140°, and 70°. The interior angles of an irregular quadrilateral are x°, 80°, 2x°, and 70°. Let’s work on a few example problems about quadrilaterals. For example, crossed trapezoid, crossed rectangle, crossed square, etc. There is another less common type of quadrilaterals, called complex quadrilaterals. Concave quadrilaterals: These are the quadrilaterals with at least one interior angle greater than 180 degrees, and at least one of the two diagonals is outside the quadrilaterals.They include trapezium, parallelogram, rhombus, rectangle, square, kite, etc. Convex quadrilaterals: These are the quadrilaterals with interior angles less than 180 degrees, and the two diagonals are inside the quadrilaterals.The quadrilaterals are classified into two basic types: The rectangle and rhombus are not square.A square is both a rhombus and a rectangle.Rectangles, rhombus, and squares are all types of parallelograms.Sum of interior angles = 180 ° * (n – 2), where n is equal to the number of sides of the polygon The sum of interior angles of a quadrilateral fits the formula of polygon i.e.The total measure of all the four interior angles of a quadrilateral is always equal to 360 degrees.Every quadrilateral has 4 sides, 4 vertices, and 4 angles.4.The properties of quadrilaterals include:

The diagonals in a kite bisect each other at right angles.

The perpendicular line DM is the height ( h) of the trapezium, while BD and CA are the bases.Ī kite is a quadrilateral with two pairs of side lengths, and these sides are adjacent to each other. The sides of a trapezium are known as bases, and the perpendicular line from any vertex of the trapezium to the base is known as the height.ĪBCD is a trapezium in which side BD is parallel to side CA. The diagonals AC = BD, and M is the point of intersection of the two diagonals.Ī trapezium or a trapezoid is an equilateral with one pair of opposite parallel sides. The Opposite sides of a rhombus are equal and parallel, and the opposite angles are the same.ĪBCD is a rhombus in which AB is parallel and equal to DC and AD is also parallel and equal to BC.

Therefore, length PM = MR, & length SM = MQĪ rhombus is a quadrilateral with all four sides having equal lengths. Point M is the midpoint of the two diagonals of the parallelogram. In the parallelogram PQRS, side PQ is parallel to side SR, and side PS is parallel to side QR. Similarly, the opposite angles in a parallelogram are equal in measure. Real-life examples of squares include computers, keys, coasters, spaces on a chessboard, etc.Ī parallelogram is a quadrilateral with 2 pairs of parallel opposite and equal sides. All angles are right angles by definition.In a square, both pairs of opposite sides are parallel and equal in length. Their right angles make sure built things such as houses, office buildings, schools, etc., stand straight and tall.Ī square is a quadrilateral with 4 right angles (90°). Rectangles are easy to stack because they have two pairs of parallel sides. For example, shoe boxes, chopping boards, sheets of paper, picture frames, etc., are rectangular in shape. Rectangles are very handy to have around. In a rectangle, both the pairs of opposite sides are parallel and equal in length. Some of the quadrilaterals are surely familiar to you, while others may not be so familiar.Ī rectangle is a quadrilateral with 4 right angles (90°). There are six quadrilaterals in geometry. The list of real-world examples of quadrilaterals is endless. Quadrilaterals are everywhere! From the books, chart papers, computer keys, television, and mobile screens. In simple words, a quadrilateral is a shape with four sides. Therefore a quadrilateral is a closed two-dimensional polygon made up of 4-line segments. How the different types of quadrilaterals look like.Īs the word suggests, ‘ Quad’ means four and ‘ lateral’ means side.We call these 4-sided shapes the quadrilaterals. Many shapes have 4 sides, but the difference in angles on their sides makes them unique. Different types of shapes differ from each other in terms of sides or angles.

Quadrilateral shapes geometry equations