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  • 三角形边长分类


    lesson content

    ::[图1]

    Tasha goes sailing with her father on her father's old boat. The sail looks like a  triangle . All of the sides of the sail are different lengths. Tasha wants to classify the triangle but she isn't sure how to name it. Given the side lengths of the triangle, how can Tasha classify the triangle?
    ::Tasha和她父亲在她父亲的旧船上航行,帆看起来像三角形。帆的两侧长度不同。Tasha想对三角形进行分类,但不确定如何命名。鉴于三角形的侧长,Tasha如何对三角形进行分类?

    In this concept, you will learn how to   by their side lengths.

    ::在这个概念中,你将学会如何与它们交错开来。

    Classifying Triangles by Side Lengths
    ::按边长对三角形进行分类

    You can use the lengths of the sides to help you classify triangles.
    ::您可以使用边的长度来帮助您分类三角形。

    Let’s look at how to classify triangles according to side length.
    ::让我们看看如何按照边长对三角形进行分类。

    An   has side lengths that are the same. Here is an example.
    ::一个侧边长度相同。这里举一个例子。

    lesson content

    These little lines let you know that the side lengths are the same. Sometimes you will see these and sometimes you won’t. You may have to figure it out on your own or by measuring with a ruler.
    ::这些小线条让你知道侧边长度是一样的。 有时你会看到这些,有时你不会。 你可能需要自己或用尺子衡量。

    A  scalene triangle  is a triangle where the lengths of all three sides are different. Here is an example of a scalene triangle.
    ::缩放三角形是三边长度不同的三角形。这里是缩放三角形的示例。

    lesson content

    You can see that all three sides of the triangle are different lengths. 
    ::你可以看到三角形的所有三边 都有不同的长度。

    An  isosceles triangle  has two side lengths that are the same and one side length that is different. Here is an example of an isosceles triangle.
    ::等分形三角形有两个侧长,两个侧长相同,一个侧长不同。这里是一等分形三角形的例子。

     

    lesson content

    Examples
    ::实例

    Example 1
    ::例1

    Earlier, you were given a problem about Tasha and her sail.
    ::早些时候,你对塔莎和她的帆感到困扰。

    Her sail is shaped like a triangle with different side lengths. What classification should Tasha give the triangle?
    ::她的帆形像三角形,侧长不同。Tasha应该给三角什么分级?

    First, determine if any of the side lengths are the same.
    ::首先,确定侧边长度是否相同。

    No
    ::否 无

    Then, classify the triangle.
    ::然后,分类三角形。

    Scalene
    ::缩缩缩

    The answer is a scalene triangle.
    ::答案是一个缩放三角形 。

    Example 2
    ::例2

    Classify this triangle as scalene, isosceles or equilateral according to its side lengths.
    ::根据三角形的侧边长度,将三角形分类为缩放、等距或等距。

    Side lengths, 6 cm, 4 cm, 6 cm
    ::长长6厘米、4厘米、6厘米

    Angles  70, 70, 40 degrees
    ::角度70,70,40度

    First, determine if any of the side lengths are the same.
    ::首先,确定侧边长度是否相同。

    Yes
    ::是 是

    Next, determine how many side lengths are the same.
    ::接下来,决定副长度是多少相同。

    Two
    ::二号

    Then, classify the triangle.
    ::然后,分类三角形。

    Isosceles
    ::同位素

    The answer is an isosceles triangle.
    ::答案是一个等分形三角形。

    Example 3
    ::例3

    Classify this triangle according to its side lengths.
    ::根据三角形的侧边长度对三角形进行分类。

    lesson content

    First, determine if any of the side lengths are the same.
    ::首先,确定侧边长度是否相同。

    No,
    ::没有

    Then, classify the triangle.
    ::然后,分类三角形。

    Scalene
    ::缩缩缩

    The answer is a scalene triangle.
    ::答案是一个缩放三角形 。

    Example 4
    ::例4

    Classify the triangle according to its side lengths.
    ::根据三角形的侧边长度对三角形进行分类。

     

    lesson content

    First, determine if any of the side lengths are the same.
    ::首先,确定侧边长度是否相同。

    Yes
    ::是 是

    Next, determine how many side lengths are the same.
    ::接下来,决定副长度是多少相同。

    All of the side lengths are the same
    ::所有侧边长度都是相同的

    Then, classify the triangle.
    ::然后,分类三角形。

    Equilateral
    ::等边

    The answer is an equilateral triangle.
    ::答案是一个等边三角形。

    Example 5
    ::例5

    Classify the triangle according to its side lengths.
    ::根据三角形的侧边长度对三角形进行分类。

     

    lesson content

    First, determine if any of the side lengths are the same.
    ::首先,确定侧边长度是否相同。

    Yes
    ::是 是

    Next, determine how many side lengths are the same.
    ::接下来,决定副长度是多少相同。

    Two
    ::二号

    Then, classify the triangle.
    ::然后,分类三角形。

    Isosceles
    ::同位素

    The answer is an isosceles triangle.

    ::答案是一个等分形三角形。

    Review
    ::回顾

    Answer the following questions using what you have learned about triangles their angles and side lengths.
    ::使用您了解的三角形的角度和侧边长度回答下列问题。

    1. If a triangle is a right triangle, then how many angles are acute?
      ::如果三角形是一个右三角形,那么有多少角度是急性的?
    2. How many angles in a right triangle are right angles?
      ::右三角形中有多少角度是右角?
    3. How many degrees are there in a right triangle?
      ::右三角形有多少度?
    4. What is an obtuse angle?
      ::什么是隐蔽角度?
    5. How many obtuse angles are in an obtuse triangle?
      ::隐形三角形中有多少隐形角度?
    6. If there is one obtuse angle, how many angles are acute?
      ::如果有一个模糊角度,有多少角度是急性的?
    7. If a triangle is equiangular, what is the measure of all three angles?
      ::如果三角形是正方形,那么所有三个角度的度量是多少?
    8. What does the word “interior angle” mean?
      ::" 内向角度 " 一词是什么意思?
    9. True or false. The side lengths of a scalene triangle are all equal.
      ::弧度三角形的侧长均相等。
    10. True or false. The side lengths of a scalene triangle are all different.
      ::弧度三角形的侧边长度都不同。
    11. True or false. The side lengths of an equilateral triangle are all equal.
      ::真实或虚假。 等边三角形的侧边长度都是相等的 。
    12. True or false. An isosceles triangle has two side lengths the same and one different.
      ::真实或假的。 等分形三角形有两个侧长相同和一个不同的侧长。
    13. True or false. A scalene triangle can also be an isosceles triangle.
      ::弧度三角形也可以是等分形三角形。
    14. True or false. An equilateral triangle is also equiangular.
      ::等边三角形也是等角三角形
    15. True or false. A scalene triangle can not be an acute triangle.
      ::缩放三角形不能是急性三角形 。

    Review (Answers) 
    ::回顾(答复)

    Click   to see the answer key or go to the Table of Contents and click on the Answer Key under the 'Other Versions' option.
    ::单击可查看答题键, 或转到目录中, 单击“ 其他版本” 选项下的答题键 。

    Resources
    ::资源