Interior and Exterior of an Angle

Interior and exterior of an angle is explained here.

The shaded portion between the arms BA and BC of the angle ABC can be extended indefinitely.

Interior and Exterior of an Angle



This portion is called the interior of the angle. X is a point in the interior of the angle. The point Y lies in the exterior of the angle. 

The point Z lies on the angle.

Interior and Exterior of an Angle



In the above figure, here ∠1 is called the interior angle because it lies inside the two arms. ∠2 is called the exterior angle. Whenever two rays meet, two angle are formed – one an interior angle and other an exterior angle. The size of an angle is measured by the amount of turn or rotation of two arms and not by how long the arms appear to be.

Interior and Exterior of an Angle

Here ∠a is greater than ∠b, ∠b is greater than ∠c.


Let ∠XOY be an angle in the plane. The rays OX and OY divide all the points of the plane in three regions (as shown in the below figure).

Interior and Exterior of an Angle

Now, we have the following:

(i) The region shown by the shaded part is the interior of ∠XOΥ.

(ii) The region of all the points, which do not lie in the interiors well as on its arms, is called the exterior of ∠XOY.

(iii) The region of all those points which lie on the arms OX and OY is called the common boundary of the two regions.

In the above figure, points P and R are in the exterior of ∠XOY, Q is in the interior of ∠XOY and O, B, S, X, Y lie on the boundary of ∠XOY.


Notes:

1. The arms of an angle separate its interior and exterior.

2. The interior of an angle together with its boundary is called the angular region of the angle

You might like these

● Angle.

Interior and Exterior of an Angle.

Measuring an Angle by a Protractor.

Types of Angles.

Pairs of Angles.

Bisecting an angle.

Construction of Angles by using Compass.

Worksheet on Angles.

Geometry Practice Test on angles.




5th Grade Geometry Page

5th Grade Math Problems

From Interior and Exterior of an Angle to HOME PAGE




Didn't find what you were looking for? Or want to know more information about Math Only Math. Use this Google Search to find what you need.



New! Comments

Have your say about what you just read! Leave me a comment in the box below. Ask a Question or Answer a Question.

Share this page: What’s this?

Recent Articles

  1. Word Problems on Area and Perimeter | Free Worksheet with Answers

    Jul 26, 24 04:58 PM

    word problems on area and perimeter

    Read More

  2. Worksheet on Perimeter | Perimeter of Squares and Rectangle | Answers

    Jul 26, 24 04:37 PM

    Most and Least Perimeter
    Practice the questions given in the worksheet on perimeter. The questions are based on finding the perimeter of the triangle, perimeter of the square, perimeter of rectangle and word problems. I. Find…

    Read More

  3. Perimeter and Area of Irregular Figures | Solved Example Problems

    Jul 26, 24 02:20 PM

    Perimeter of Irregular Figures
    Here we will get the ideas how to solve the problems on finding the perimeter and area of irregular figures. The figure PQRSTU is a hexagon. PS is a diagonal and QY, RO, TX and UZ are the respective d…

    Read More

  4. Perimeter and Area of Plane Figures | Definition of Perimeter and Area

    Jul 26, 24 11:50 AM

    Perimeter of a Triangle
    A plane figure is made of line segments or arcs of curves in a plane. It is a closed figure if the figure begins and ends at the same point. We are familiar with plane figures like squares, rectangles…

    Read More

  5. 5th Grade Math Problems | Table of Contents | Worksheets |Free Answers

    Jul 26, 24 01:35 AM

    In 5th grade math problems you will get all types of examples on different topics along with the solutions. Keeping in mind the mental level of child in Grade 5, every efforts has been made to introdu…

    Read More