Distinguishing Angles: Acute, Right, Obtuse, and Straight

Angles get created whenever \(2\) lines overlap at a point. Then, the measure of the ‘opening’ in-between those \(2\) rays is known as an ‘angle’. It’s shown via the symbol \(∠\).

Angles normally get measured via degrees and radians, and this is a measure of circularity or rotation.

We see angles every day as engineers, as well as architects, utilize angles to design buildings, roads, as well as sporting facilities.

There are \(2\) main components associated with angles – the arms and the vertex.

Related Topics

• Triangles
• How to Find Vertical Angles?
• How to Solve Unknown Angles?
• How to Construct Triangles?

Angle Arms

The \(2\) rays that link up at a common point and create an angle are known as angle arms.

Vertex of an angle

Vertex is a commonplace endpoint shared by the \(2\) rays.

Angle measurement

Angles get measured in degrees. One complete rotation around a point creates a complete angle of \(360°\).

Kinds of Angles and Properties

Six kinds of angles exist. Each one comes with its specific identification of the source of angle measurement. Let’s find out about each one of these kinds of angles separately along with the properties they have.

Acute Angles

Acute angles are angles with a measurement bigger greater than \(0°\) and lower than \(90°\).

Right Angles

Whenever an angle measures \(90°\), it’s called a right angle. Right angles can be easily known since they form the shape of the letter \(L\).

Obtuse Angles

Whenever an angle measures lower than \(180°\) yet bigger than \(90°\) it’s called an obtuse angle.

Straight Angles

Angles created via straight lines are called straight angles. Straight angles are made with straight lines, and an angle created in-between \(2\) rays are equivalent to \(180°\). With straight angles, the \(2\) rays are opposite of one another. Two right angles create a straight angle. Because the measurement of a straight angle is \(180°\), it’s one-half of the complete turn of a circle.

Reflex Angles

Reflex angles are angles that measure more than \(180°\) yet lower than \(360°\).

Complete Angles

Whenever an angle’s measurement is equivalent to \(360°\) it’s a complete angle.

Missing Numerals – Example 1:

Write the name of the angle.

Solution:

This angle measures lower than \(180°\) yet bigger than \(90°\). So, it’s an obtuse angle.

Missing Numerals – Example 2:

Write the name of the angle.

Solution:

This angle measure more than \(180°\) yetis lower than \(360°\). So, it’s a Reflex angles.

Exercises for Missing Numerals

Write the name of the angles.

1)

2)

1. \(\color{blue}{Acute}\)
2. \(\color{blue}{Right}\)