Another type of triangle is an obtuse triangle. This is where one of the angles of the triangle is more than 90 degrees.

Here's an example of an obtuse triangle in everyday life.

Remember that an obtuse angle is an angle that is greater than 90 degrees but less than 180 degrees.

In the triangle shown above, the angle in the lower left-hand corner is more than 90 degrees. It is 110 degrees. This makes this triangle obtuse.

Try This:

Draw an obtuse angle with a ruler and a protractor. Remember it is an angle greater than 90 degrees but less than 180 degrees. Then make it into an obtuse triangle by drawing in the third side. Share with your teacher when done.

Here's a question for you to think about. Are the other angles in the obtuse triangle you drew acute, obtuse, or right angles?