角度分类

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[Figure 1]

::[图1]

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Claire's art teacher gave her an image and asked her to make a painting that recreates the image. Claire likes to paint general shapes as her starting points and then draws in more details later. The first shape that she notices is the hat on the woman's head. She sees that the hat looks like an  angle . If Claire recreates the angle on her painting, will she have a  right angle ,  straight angle ,  acute angle  or an  obtuse angle ?
::Claire的艺术老师给了她一个图像, 并要求她画一幅画来重建图像。 Claire喜欢画一般形状作为她的起点, 然后再绘制更多细节。 她注意到的第一种形状是女人头上的帽子。 她看到帽子看起来像一个角度。 如果Claire重新塑造了画上的角度, 她会有一个正确的角度, 直角, 急性角度或者模糊角度吗?

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In this concept, you will learn about angle classifications.
::在这个概念中,你会了解角度分类。

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Classifying Angles
::分类分类角度

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An  angle  is formed when two rays connect at a single  endpoint . You can  measure  an angle in degrees. When measuring an angle, you are measuring the  space  between the two rays.
::当两个射线在单一端点连接时形成一个角度。您可以测量一个角度的度。当测量一个角度时,您正在测量两个射线之间的空间。

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The  arc  represents the space of the angle that you are measuring. This angle is very small as you can see by the size of the arc.
::弧表示您正在测量的角度的空间。 这个角度很小, 您从弧的大小可以看到 。

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This arc is very large. The space between the rays is large so the angle is large too.
::这个弧非常大。 射线之间的空间很大, 所以角度也很大 。

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You can classify or organize angles according to the size of the angle. The size of the angle is classified according to the number of degrees.
::您可以根据角度的大小对角度进行分类或组织角度。角的大小根据度数进行分类。

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There are 4 major types of angles.
::有四种主要角度类型。

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A  right angle  is an angle that is exactly 90 degrees. It is easy to recognize because it forms a corner that is straight. Often with a right angle you will see a little box in the corner too.
::右角是一个精确为 90 度的角。 很容易识别, 因为右角是一个直角。 通常用右角, 您也会在角中看到一个小盒子 。

 

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An  acute angle  is an angle that is greater than 0 degrees but less than 90 degrees. Here is an example of an acute angle.
::急性角是一个大于 0 度但小于 90 度的角。这里是一个急性角的例子 。

 

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A  straight angle  is the same as a straight  line . A straight line is equal to  $\begin{array}{r}{180}^{\circ }\end{array}$ . The angle of a straight line stretches from one side of the line to the other side as indicated by the arc in this picture.
::直角与直线相同。直线等于 180 。直线的角从直线的一面延伸至另一侧,如此图中弧形所示。

 

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An  obtuse angle  is an angle that is greater than 90 degrees but less than 180 degrees. Here is an example of an obtuse angle.
::斜角是一个大于90度但小于180度的角。这里是一个斜角的例子。

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Examples
::实例

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Example 1
::例1

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Earlier, you were given a problem about Claire and her painting.
::早些时候,你得到一个问题 关于克莱尔和她的画。

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Claire sees the angle of the woman's hat. Look at the top  point  of the hat and the angle as the hat moves down to her head.  Is the angle a right angle, straight angle, acute angle or an obtuse angle?
::Claire看到女人帽子的角。 看看帽子的顶端和帽子向下向头移动的角度。 角是右角、 直角、 急角还是斜角?

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First, determine the angle's relationship to 90 degrees.
::首先,确定角度与90度的关系。

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Less than 90
::90岁以下

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Then, name the angle.
::然后,请说出角度。

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Acute
::急性

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The answer is acute angle. The hat looks like an acute angle.
::答案是急性角度 帽子看起来像急性角度

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Example 2
::例2

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Is the following angle acute, obtuse, right or straight?
::下面的角是尖锐的,隐蔽的,是正的还是直的?

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First, determine the angle's relationship to 90 degrees.
::首先,确定角度与90度的关系。

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Greater than 90
::90岁以上

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Then, name the angle.
::然后,请说出角度。

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Obtuse
::阻力

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The answer is an obtuse angle.
::答案是一个隐蔽的角度。

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Example 3
::例3

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Is the following angle acute, obtuse, right or straight?
::下面的角是尖锐的,隐蔽的,是正的还是直的?

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First, determine the angle's relationship to 90 degrees.
::首先,确定角度与90度的关系。

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Less than 90
::90岁以下

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Then, name the angle.
::然后,请说出角度。

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Acute
::急性

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The answer is acute angle.
::答案是尖锐的角度。

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Example 4
::例4

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Is the following angle acute, obtuse, right or straight?
::下面的角是尖锐的,隐蔽的,是正的还是直的?

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First, determine the angle's relationship to 90 degrees.
::首先,确定角度与90度的关系。

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Equal to 90
::平等 至 90

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Then, name the angle.
::然后,请说出角度。

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Right
::右右右

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The answer is a right angle.
::答案是正确的角度。

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Example 5
::例5

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Is the following angle acute, obtuse, right or straight?
::下面的角是尖锐的,隐蔽的,是正的还是直的?

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First, determine the angle's relationship to 90 degrees.
::首先,确定角度与90度的关系。

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Greater than 90
::90岁以上

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The, name the angle.
::来 点个角度

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Obtuse
::阻力

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The answer is an obtuse angle.

::答案是一个隐蔽的角度。

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Review
::回顾

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Classify each angle as acute, right, obtuse or straight.
::将每个角度分类为急性、右、隐形或直角。

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1. 

   [Figure 12]
   
   ::[图12]
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2. 

   [Figure 13]
   
   ::[图13]
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3. 

   [Figure 14]
   
   ::[表14]
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4. 

   [Figure 15]
   
   ::[图15]
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5. An angle measuring  $\begin{array}{r}{88}^{\circ }\end{array}$
   ::角度 88
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6. An angle measuring  $\begin{array}{r}{90}^{\circ }\end{array}$
   ::测量 90 的角 90
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7. An angle measuring  $\begin{array}{r}{180}^{\circ }\end{array}$
   ::一个角度,测量180 {____________________________________________________________________________________________________
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8. An angle measuring  $\begin{array}{r}{105}^{\circ }\end{array}$
   ::角测量 105
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9. An angle measuring  $\begin{array}{r}{118}^{\circ }\end{array}$
   ::角度 118
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10. An angle measuring  $\begin{array}{r}{5}^{\circ }\end{array}$
    ::一个角度, 测量 5
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11. An angle measuring  $\begin{array}{r}{17}^{\circ }\end{array}$
    ::测量 17 的角 17
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12. An angle measuring  $\begin{array}{r}{135}^{\circ }\end{array}$
    ::角测量 135 {_________________________________________________________________________________________________________
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13. An angle measuring  $\begin{array}{r}{75}^{\circ }\end{array}$
    ::a 角度, 测量 75
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14. An angle measuring  $\begin{array}{r}{5}^{\circ }\end{array}$
    ::一个角度, 测量 5
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15. An angle measuring  $\begin{array}{r}{15}^{\circ }\end{array}$
    ::一个角度, 测量 15

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Review (Answers)
::回顾(答复)