We can observe that in all instances, an obtuse angle is formed between the hour's hand and the minutes' hand of the clock. Example 3: Can an obtuse angle triangle have sides measuring 4 units, 5 units, and 8 units? In an obtuse triangle, the sum of the square of two sides should be less than the square of the greatest side i. Hence, the given measures form an obtuse angle triangle. Therefore, the sides measuring 4 units, 5units and 8 units form an obtuse triangle.
In geometry, we read about various types of angles. Each type of angle has its own characteristic with the help of which we can identify it. Similarly, an obtuse angle is an angle that is always less than degrees and is greater than 90 degrees. We can use a protractor and verify the same. Learn Practice Download. Obtuse Angle Obtuse angle is one of the types of angles that form on the plane surface.
What Is an Obtuse Angle? Obtuse Angle Degree 3. Examples of Obtuse Angles 4. Obtuse Angle of a Triangle 5. Obtuse Angles of a Rhombus 6. Obtuse Angles of a Parallelogram 7. Obtuse Angle Examples Example 1: Identify the obtuse angles from the following figures.
Example 2: At what times, in the clocks shown below, an obtuse angle is formed? Solution: We can observe that in all instances, an obtuse angle is formed between the hour's hand and the minutes' hand of the clock.
At , the hour hand is at 5 and the minute hand is at At , the hour hand is at 8 and the minute hand is at At , the hour hand is at 10 and the minute hand is at 3. At , the hour hand is slightly above and the minute hand is at 8.
Therefore, an obtuse angle is formed at , , , and Solution: In an obtuse triangle, the sum of the square of two sides should be less than the square of the greatest side i. Want to build a strong foundation in Math? Experience Cuemath and get started. And the terminology I want to introduce you to are acute angles, right angles, and obtuse angles.
And I think when we just go through these, they'll be pretty self-explanatory. An acute angle is an angle-- well, let me just draw them first. Then it might start to make sense. So an acute angle will look something like that. I draw two rays that are coming from a common point. So the acute angle will be this angle right over here.
I could also draw an acute angle, maybe an angle that's formed from the intersection of two lines. This angle will be acute, and so will this angle. They're both acute angles. And we're going to see is acute angles are ones that are-- since I haven't defined right angles yet-- they're narrower. And what we're going to see is that they're smaller than right angles. Right angles are when the rays or the lines are going, I guess, in the-- I don't want to use the word, right, in my definition-- but if one is going horizontal, the other one will be going vertical.
So let me draw it with the rays first. So the right angle, this one's going from the left to the right. Then the other ray is going from the bottom to the top. This angle right over here is a right angle. And I could label it like that, as a traditional angle. But the general convention for labeling right angles is to put a little, kind of a half of a box right over there. And that means that is a right angle. Or that if this is going left to right, this is going perfectly top to bottom, that this is in no way kind of-- I guess the best way to think about it and why it's called right is that this ray is completely upright, compared to this ray over here.
And let me draw it with some lines. So if I have one line like this and then I have another line like that, a right angle over here-- actually all of these would have to be right angles-- it would mean that this line is completely-- if this was the ground, this line is completely upright, relative to this line over here. So either of these, that's what a right angle means.
And now that we've defined right angle, I can give you another definition for an acute angle. An acute angle has a measure, or it's smaller, than a right angle. When you learn about radians and degrees, which are different ways to measure angles, you'll see that a right angle can be measured as 90 degrees.
This over here is less than 90 degrees. So this is less than 90 degrees. And one way to conceptualize this is that this angle, its opening is smaller, it's more narrow, the lines are-- you would have to rotate one line less to get to the other line than you would over here.
Here, you'd have to move it all the way over there. Here, you'd only have to move it a little bit. So the acute angle is less than a right angle. And so you might imagine already what an obtuse angle is. It is greater than a right angle. So let me draw a couple of examples of obtuse angles. So an obtuse angle might look like-- let me make it a little bit clearer. It might look like that.
If this was a right angle, this line over here would look something like that.
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