Skip to main content
Search IntMath
Close

Exploring Obtuse Triangles in Geometry 

When it comes to geometry, understanding the different types of triangles is key. This blog post will discuss obtuse triangles specifically, what they are, why they are important, and how to calculate their angles and sides.

What is an Obtuse Triangle? 

An obtuse triangle is a triangle with one angle that measures greater than 90 degrees. This type of triangle has two acute angles (measuring less than 90 degrees) and one obtuse angle (measuring greater than 90 degrees). The sides of an obtuse triangle are also unequal in length; that is, the longest side of an obtuse triangle is always opposite the obtuse angle. 

Why Study Obtuse Triangles?

Obtuse triangles can be useful when studying right triangles because they can be used to calculate certain types of right angles. For example, if you have an unknown right angle and know the lengths of two sides of the triangle, you can determine if the angle is a right angle by measuring its third side. If it's longer than either of the other two sides, then it must be an obtuse triangle and thus not a right triangle.  Calculating Angles and Sides in Obtuse Triangles To find out how long each side is in an obtuse triangle, use the Pythagorean theorem – a^2 + b^2 = c^2 – where ‘a’ and ‘b’ represent two known side lengths and ‘c’ represents the remaining unknown length. You can also use trigonometric functions like sine or cosine to calculate angles within an obtuse triangle if you know the lengths of all three sides. 

Conclusion

In conclusion, obtuse triangles are important for calculating angles in right triangles as well as for understanding some fundamental concepts about triangles and geometry more

FAQ

 

What is an example of an obtuse triangle?

An example of an obtuse triangle is a triangle with sides that measure 3, 4, and 5 units in length. The angle opposite the longest side (5 units) would be greater than 90°, making it an obtuse triangle.

What is an obtuse example?

An example of an obtuse triangle is one with angles measuring 91 degrees, 45 degrees, and 44 degrees. The longest side of the triangle is opposite the 91-degree angle.

Tips, tricks, lessons, and tutoring to help reduce test anxiety and move to the top of the class.

top