特殊角对角

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In This Lesson
::在本课程中

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You will learn about different types of angles and how to classify them. Some of this may be review for you.
::您将学习不同角度的种类以及如何分类。 其中一些可能是对您的评论 。

 

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Lines and Angles Vocabulary
::线条和圆形词汇

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A line   is composed of infinitely many points, but you only need two points to  define a line. Similarly , you need two points to define a line segment  or a ray . Three points are collinear if they lie on the same line. 
::线条由无限多的点组成, 但只需要两个点来定义线条。 同样, 您也需要两个点来定义线条段或射线。 如果三点位于同一线条上, 则三点是圆线的 。

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An angle is defined as two rays that share an endpoint . That point is called the vertex of the angle. Three points are used to define an angle, where the middle point is always the vertex.
::角被定义为两个共享端点的射线。该点被称为角的顶点。使用三个点来定义角,其中中点总是顶点。

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The following questions are based on the diagram above.
::以下问题以上图为基础。

 

 

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N ote that if there is only one angle at a vertex, it could be labeled  using   just the  vertex point. Also, some diagrams will label angles with numbers, such as  $\begin{array}{r}\mathrm{\angle }1\end{array}$ ,  $\begin{array}{r}\mathrm{\angle }2\end{array}$ , and so on.  The  number will always be inside the angle  and  typically be a different color than the letters .
::请注意, 如果顶点上只有一个角度, 只需使用顶点就可以贴上标签 。 另外, 一些图表会标记数字角度, 如 1, 2 等 。 数字总是在角度内, 通常与字母颜色不同 。

播放段落 This angle can be labeled  $\begin{array}{r}\mathrm{\angle }B\end{array}$  because that is the only angle with a vertex at point  $\begin{array}{r}B.\end{array}$ ::此角度可以标签为 {B} , 因为它是唯一在 B 点带有顶点的角 。	播放段落 This angle can be labeled  $\begin{array}{r}\mathrm{\angle }5\end{array}$ .  Notice that this angle is NOT 5°.   ::此角度可以标注 #% 5. 注意此角度不是 5 度 。

 

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Vertical and Adjacent Angles
::垂直和相近角

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When two lines interact,  four  angles are created.  Two angles that are opposite each other such that they share a vertex and do not share any sides are called .  Two  angles that share one side  and a vertex are called adjacent angles because they are next to each other.
::当两个线条互动时,将创建四个角度。两个对立的角度,即它们共享一个顶点,不共享任何侧面。两个共享一边的角和一个顶点被称作相邻角度,因为它们彼此相邻。

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Using the picture below, determine which pairs are vertical angles and which are adjacent angles. Then  drag the lines around and see how the angle measures change.
::使用下面的图片, 确定哪一对是垂直角度, 哪些是相邻角度。 然后拖动周围的线条, 并查看角如何测量变化 。

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What do you notice about the angle measures of the vertical angles? for more examples of vertical angles!
::您注意到垂直角度角度的角度量吗 ? 更多垂直角度的例子 !

 

 

 

 

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Recall that angles are always measured in degrees. As you saw when you moved the line around the vertex, the vertical angles remained equal. This is always true:  vertical angles have equal measures .  
::提醒注意角度总是以度量度衡量。 正如您移动顶点周围的线条时所看到的, 垂直角度仍然相等 。 这总是对的: 垂直角度具有等量度 。

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Two angles are complementary if they add up to 90°. That means if two angles are adjacent and within a right angle , they would also be complementary. When an angle is marked with a small square (inside the angle), that means that the angle measures 90°, or is a right angle.
::两个角度如果加起来等于90°,是互补的。这意味着如果两个角度相邻,在一个右角度内,它们也是互补的。当一个角度用一个小方形标记(角的侧面),这意味着角等于90°,或者是一个右角度。

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Two angles are supplementary if they add up to 180°. This means that if two angles are adjacent and within a straight angle , they will be supplementary. There is no angle marking to label a straight angle.  You may assume that a line is a straight angle.
::两个角度如果加起来等于180°,是补充的。这意味着如果两个角度相邻,在直角内,它们将是补充的。没有角标记可以标出直角。您可以假定一条线是一个直角。

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Note that two angles  can be complementary or supplementary even if they are not equal or adjacent.
::请注意,两个角度即使不相等或相邻,也可以相互补充或补充。

 

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Using Angle Pairs
::使用角对角

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Use this interactive to  move around point $\begin{array}{r}L\end{array}$  such that it lands in circle  $\begin{array}{r}M\end{array}$  and then in circle  $\begin{array}{r}N.\end{array}$  You can also move around point  $\begin{array}{r}A,\end{array}$  such that it lands in circles  $\begin{array}{r}C\end{array}$  and  $\begin{array}{r}D.\end{array}$
::使用此互动方式在 L 点周围移动, 让它在 M 圈内降落, 然后在 N 圈内。 您也可以在 A 点周围移动, 让它在 C 和 D 圈内降落 。