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  • 书写双级平方

    In This Lesson
    ::在本课程中

    Until now, you have been dealing mostly with algebraic expressions. In this lesson, you will shift to algebraic equations. You may already know how to solve basic equations and this lesson will build upon that. An algebraic equation is a pair of expressions joined by an equal sign. In this text, one of the expressions will not have variables, so it will only be constants or combinations of constants. 
    ::直到现在, 您一直主要处理代数表达式 。 在此课中, 您将转换为代数方程 。 您可能已经知道如何解析基本方程, 此课将以此为基础。 代数方程是一对配以等号的表达式。 在此文本中, 表达式中有一个将没有变量, 因此只能是常数或常数组合 。

     

    Matching Equations
    ::匹配方程

    What is the answer to: "5 more than a number is 7"?  What about "2 less than a number is -5"?  In this interactive, there are phrases like this, and you will need to match the phrase with the equation . 
    ::答案是:“5比数字7多5”?“2比数字少5”是什么意思?在这个互动的语句中,有这样的语句,你需要将这个语句与等式相匹配。

     

     

     

     

    As you discussed, it does not matter which side of the equal sign that you write which expressions. As long as the expression is correct, the side does not matter. In addition , remember that a fraction is a division problem. And, when a coefficient is in front of a variable (without a sign in between them), these two numbers are being multiplied .
    ::正如你们讨论过的那样, 您写入哪个表达式的相同符号的哪个侧面并不重要。 只要表达式正确, 则该侧面并不重要 。 此外, 请记住一个分数是一个分割问题 。 当变量面前的系数( 在变量之间没有符号) 时, 这两个数字会乘以 。

    Discussion Question
    ::讨论问题

    Harris thinks it is easier to solve an equation with the variable on the left side. Do you agree or disagree? Does it matter?
    ::哈里斯认为用左侧的变量解方程比较容易。 您同意还是不同意? 这重要吗 ?

     

    Back to School Shopping
    ::回学校购物

    Jeanne needs to buy shirts to look good when she goes back to school in a couple of weeks. She has $55 to spend, and all the shirts are conveniently the same price at her favorite store. She purchased 5 shirts and left the store with $7.50. How much did each shirt cost?
    ::珍妮在几周内回到学校时需要买衬衫才能看起来好。她有55美元要花,而且所有衬衫的价格都与她最喜欢的商店的价格相当。她购买了5件衬衫,离开商店时有7.50美元。每件衬衫要花多少钱?

    Use this interactive to create the equation for Jeanne's shirts and then find the value of  s (cost of shirts) that will make the equation true.
    ::使用此互动来创建 Jeanne 衬衫的方程式, 然后找到使方程式真实的 s( 衬衫成本) 值 。

     

     

     

     

     

    What Are the Words?
    ::语言是什么?

    Create a real-world situation that goes with this equation:  25 + 15 x = 85 . First, analyze the equation. What does each part represent?
    ::创建符合此方程式的真实世界状态 : 25+15x=85。 首先, 分析方程。 每个部分代表什么 ?

    In the interactive below, match each term or variable with what it means.
    ::在下文互动部分,将每个术语或变量与其含义相匹配。

     

     

    Now that you know what each part of the equation represents, determine a story or word problem that can go along with it. There are several verbal phrases below that you can put into sentences so that they can go along with the equation. Make sure your word problem makes sense and be creative. You will need to insert an "and" so that your word problem flows nicely.
    ::现在你知道方程的每个部分代表着什么, 确定一个故事或字的问题, 并随之而来。 下面有几句话可以加到句子中, 以便它们能和方程一起来。 保证您字词的问题是有道理的, 并且具有创造性。 您需要插入一个“ 和 ” , 以便您字词的问题能够顺利地流动 。

     

     

     

     

    Discussion Question
    ::讨论问题

    What is  another possible word problem for this equation: 8 x − 3 = 21 ?  
    ::这个方程式的另一个可能的词问题是什么: 8x-3=21?

     

       Summary
    ::摘要

    • When interpreting an equation within a context, use words such as "and", "each", and "total"
      ::当在上下文中解释等式时,使用“和”,“每个”和“总计”等词
    •  A solution to an equation is a value that makes the equation true. 
      ::方程式的解决方案是一个使方程式真实的值。