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  • 对等表达式

    How Much Do the Beaded Bracelets Cost?
    ::珠盘要花多少钱?

    Arya wants to make matching bracelets for her friends. She doesn't yet know the cost of the different kinds of beads. Until she finds out the , let the star beads cost  a ¢  each and let the oval beads cost  b ¢  each.
    ::艾莉亚想为朋友们做配对手镯。她还不知道不同珠子的成本。在她发现之前,让星星珠子各花一分钱,让珠子每人花一分钱。

    Use the interactive to make the matching bracelets. Notice how the cost of the bracelets is expressed in two different ways. Use this interactive to create your own expression using the cost of beads as your variables and the number of beads as your coefficients.
    ::使用交互手镯来制作匹配的手镯。 注意手镯的成本以两种不同的方式表达。 使用此互动来创建您自己的表达方式, 使用珠子的成本作为变量, 并使用珠子的数量作为系数 。

     

     

     

     

     

    Can You Find the Areas of the Boxes?
    ::你能找到盒子的区域吗?

    lesson content
    Gift boxes

    You can find the area of any rectangle by multiplying the length by the width. In the interactive below, use the to express the area of the rectangles as two different but equivalent expressions.
    ::您可以通过将长度乘以宽度来找到任何矩形的区域。在下面的互动中,使用矩形区域表示两个不同但相当的表达式。

     

     

    Astronomical Relationship
    ::天文关系

    lesson content
    Solar System

    When astronomers measure the  time it takes planets to go around the sun, they call that amount of time the orbital period of the planet. Earth's orbital period is 1 year.  Astronomers  also measure the distance of a planet are from the sun using  a measurement called astronomical units. The distance from Earth to the sun is 1 astronomical unit.
    ::当天文学家测量行星绕太阳运行所需的时间时, 他们称这一时间为行星的轨道周期。 地球的轨道周期为1年。 天文学家还测量了行星与太阳的距离, 测量的尺度叫做天文单位。 从地球到太阳的距离是1个天文单位 。

    Use the interactive to explor e each  planet's  orbit and distance from the sun . Notice how the  time it takes to orbit  relates to the distance.  In the questions that follow, you will use equivalent expressions to find equations that help you find a planet's orbital period or distance from the Sun.
    ::使用交互方式来探索每个行星的轨道和距离太阳。 注意它进入轨道的时间与距离的关系。 在接下来的问题中, 您将使用等同的表达方式来找到公式, 帮助您找到行星的轨道周期或距离太阳的距离 。

     

     

     

    Discussion Questions
    ::讨论问题 讨论问题

    1. Do you believe this relationship holds true for the outer planets Jupiter, Saturn, Uranus, and Neptune? What information would be needed to verify this?
    ::1. 你是否认为木星、土星、天王星和海王星等外行星的这种关系是真实的?

    2. When Johannes Kepler made this discovery in the early 1600s, he believed that he had discovered the mathematical rule that determined the motion of all astronomical objects in the universe. Do you think this is true? Why or why not?
    ::2. 当约翰尼斯·开普勒在1600年代初期发现这一发现时,他相信他发现了确定宇宙中所有天文物体运动的数学规则,你认为这是真的吗?为什么或为什么不是?

     

     

    Perimeter Patterns
    ::周边模式

    lesson content
    A "pursuit curve" drawn using squares.

    How do the perimeters of squares that get smaller and smaller relate to one another? In this interactive, find the pattern and the scale factor that will create equivalent expressions for the different sized squares.
    ::变小和变小的方形周围是如何相互连接的?在此互动中,找到为不同方形创建等效表达式的模式和比例系数 。

     

     

     

     

     Summary
    ::摘要

    • Expressions can be used to represent real-world quantities 
      ::表达式可用于表示真实世界数量
    • When two expressions represent the same quantity, they are equivalent
      ::当两个表达式表示相同数量时,它们等于