# Right Angle

Angle whose measurement is exact 90 degree is right angle.

The keyword here is exact 90 degree.
It it gets more than 90, the angle will becomes obtuse.
If it gets less than 90, the angle becomes acute.

Examples of Right Angle is given below:

## Right Angle & Its Part

Right Angle is formed by joining two rays at a common point at exactly 90 degree angle.

Some important parts of Right Angle is:

(a) Arms
The two rays joining to form the angle is known as Arms.

Here OA & OB are the two arms of the angle

(b) Vertex
The common point at which the two ray join is called Vertex.

Here Point O is the vertex

## Drawing Right Angle using Protractor

In order to draw a right angle you need a device called Protractor.
Protractor can be easily purchased from the local stationary shop and its very cheap to buy.

Do the following steps for angle construction:

(a) Take a blank paper and draw a horizontal line OA

(b) Take protractor and place its center at point O (as given in figure)

(c) To make right angle you have to measure exact 90 degrees.
Find the 90 number in protractor and mark Point B

(d) Remove the protractor and join line OB

Thus we got Angle AOB = 90 degree

## Right Angle in Geometrical Figure

Some common geometrical figures that form 90 degree angle are:

(a) Square
All the angles are exactly 90 degrees

(b) Right angled triangle
Here one angle is 90 degree

(c) Pentagon
Angle C & D are the two right angles