Before talking around the quadrilaterals angle amount property, let united state recall what angles and also quadrilateral is. The edge is created when 2 line segment join at a solitary point. An edge is measured in degrees (°). Square angles space the angles developed inside the form of a quadrilateral. The square is four-sided polygon which have the right to have or not have equal sides. That is a closed number in two-dimension and also has non-curved sides. A quadrilateral is a polygon which has actually 4 vertices and also 4 political parties enclosing 4 angle and the amount of all the angles is 360°. Once we draw a attract the diagonals come the quadrilateral, it creates two triangles. Both these triangles have actually an angle sum of 180°. Therefore, the total angle sum of the quadrilateral is 360°. Edge sum is among the nature of quadrilaterals. In this article, w will find out the rules of angle amount property.

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QuadrilateralArea the Quadrilateral
Construction that QuadrilateralsTypes that Quadrilaterals

Angle Sum home of a Quadrilateral

According to the angle sum building of a Quadrilateral, the amount of every the 4 interior angle is 360 degrees.

Proof: In the quadrilateral ABCD,

∠ABC, ∠BCD, ∠CDA, and ∠DAB are the internal angles.AC is a diagonalAC divides the quadrilateral into two triangles, ∆ABC and ∆ADC

We have learned that the amount of interior angles that a quadrilateral is 360°, the is, ∠ABC + ∠BCD + ∠CDA + ∠DAB = 360°.

let’s prove the the sum of every the 4 angles the a square is 360 degrees.

We recognize that the amount of angles in a triangle is 180°.Now think about triangle ADC,

∠D + ∠DAC + ∠DCA = 180° (Sum of angle in a triangle)

Now consider triangle ABC,

∠B + ∠BAC + ∠BCA = 180° (Sum of angles in a triangle)

On including both the equations obtained above we have,

(∠D + ∠DAC + ∠DCA) + (∠B + ∠BAC + ∠BCA) = 180° + 180°

∠D + (∠DAC + ∠BAC) + (∠BCA + ∠DCA) + ∠B = 360°

We check out that (∠DAC + ∠BAC) = ∠DAB and also (∠BCA + ∠DCA) = ∠BCD.Replacing them we have,

∠D + ∠DAB + ∠BCD + ∠B = 360°

That is,

∠D + ∠A + ∠C + ∠B = 360°.

Or, the amount of angle of a square is 360°. This is the angle sum property of quadrilaterals.

Quadrilateral Angles

A quadrilateral has 4 angles. The amount of its internal angles is 360 degrees. Us can uncover the angles of a quadrilateral if we understand 3 angle or 2 angle or 1 angle and 4 lengths that the quadrilateral. In the image offered below, a Trapezoid (also a type of Quadrilateral) is shown.

The amount of every the angles ∠A +∠B + ∠C + ∠D = 360°


In the situation of square and rectangle, the value of all the angle is 90 degrees. Hence,

∠A = ∠B = ∠C = ∠D = 90°

A quadrilateral, in general, has actually sides of different lengths and angles of various measures. However, squares, rectangles, etc. Space special types of quadrilaterals with few of their sides and also angles gift equal.

Do the Opposite next in a Quadrilateral amounts to 180 Degrees?

There is no relationship between the the contrary side and also the angle procedures of a quadrilateral. To prove this, the scalene trapezium has actually the side length of various measure, which does not have opposite angles of 180 degrees. But in case of some cyclic quadrilateral, such together square, isosceles trapezium, rectangle, the opposite angles room supplementary angles. It method that the angles include up come 180 degrees. One pair of opposite square angles are equal in the kite and also two pair of the opposite angles space equal in the quadrilateral such as rhombus and also parallelogram. It means that the sum of the quadrilateral angle is equal to 360 degrees, but it is not necessary that the opposite angle in the quadrilateral have to be the 180 degrees.

Types that Quadrilaterals

There room basically five types of quadrilaterals. Castle are;

Parallelogram: Which has actually opposite sides together equal and parallel to every other.Rectangle: Which has actually equal opposite sides but all the angles space at 90 degrees.Square: Which every its four sides together equal and also angles at 90 degrees.Rhombus: that a parallelogram with all the sides as equal and its diagonals bisects each other at 90 degrees.Trapezium: Which has only one pair of sides together parallel and the sides may not be same to each other.


1. Discover the 4th angle the a square whose angles room 90°, 45° and also 60°.

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Solution: by the edge sum residential property we know;

Sum of all the inner angles the a square = 360°

Let the unknown edge be x


90° + 45° + 60° + x = 360°

195° + x = 360°

x = 360° – 195°

x = 165°

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