Date: Thu, 10 Nov 94 16:12:00 PST From: "Neufeld, Joyce CLK-STAFF" Subject: lst grader's want to know We are learning about geometric shapes. One of my students wants to know what is an obtuse angle? Joyce Neufeld First Grade Teacher Clark Elementary (for Douglas Sherbon)
Date: Fri, 11 Nov 1994 12:19:04 -0500 (EST) From: Dr. Ken Subject: Re: lst grader's want to know Hello there in Ms. Newfield's class!! You've sent in a great question. I'm VERY impressed that you're learning about different kinds of angles in first grade! Good work. You know what an angle is, right? Well, an obtuse angle is just one special kind of angle. If we look at all different kinds of angles, we can divide them up into three groups: 1) Those that look like this: | | | | | | | | |____________________ These angles are called Right Angles. If you look at the corner of a regular sheet of paper, or at the corner of the table or a blackboard, you'll find a right angle. Where else can you find a right angle? I bet there are some all around you in the classroom! 2) Angles that are smaller than right angles, like this: / / / / / / / / / / / / / /______________________ Note that when I say SMALLER, I don't mean that the lines that make them up are shorter, but that it comes to a sharper point than a right angle. All of these angles are called ACUTE angles. Can you find some around you? I be there are some. 3) The angles that are bigger than right angles, which might look like this: \ \ \ \ \ \ \ \ \ \ \ \ \____________________________ See how these two lines don't come to a very sharp point? My friend, all these angles that don't come to as sharp a point as a right angle are called OBTUSE angles. Can you find some examples of obtuse angles around you? Have fun! -Ken "Dr." Math
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