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7th Grade Math / Lesson 7: Inequalities III

INEQUALITIES
What will we be learning in this lesson?


  • In this lesson, you will learn more about inequalities and their graphs.
Vocabulary words are found in this purple color throughout the lesson. Remember to put these in your notebook.


Inequalities


  • The solutions to an inequality are the numbers that you can put in for the variables that actually work in the problem.
  • As we saw in a previous section, to determine if a number is a solution, just put the number in for the variable and see if it works.
  • What do you do if you are not given the number to check?
  • Use a method called "Guess and Check". Just pick a number that you think might work and try it. If it works, great. If not, pick another one and try again.


Inequalities


  • Use the Guess and Check method (also called mental math) to find 3 solutions for the following inequality.

    1. x - 8 < 16


Inequalities


  • Use the Guess and Check method (also called mental math) to find 3 solutions for the following inequality.

    1. x - 8 < 16

    Start by picking a number that you think might work.

    Let's try 50. Plug the number into the original inequality.

    x - 8 < 16

    50 - 8 < ? 16

    42 < ? 16

    42 is not less than 16 so this means that 50 is not a solution. 42 is too large.

    Pick another number and try again.


Inequalities


  • Use the Guess and Check method (also called mental math) to find 3 solutions for the following inequality.

    1. x - 8 < 16

    Let's try 20. Put 20 into the original inequality.

    x - 8 < 16

    20 - 8 < ? 16

    12 < ? 16

    12 is less than 16 so this means that 20 is a solution.

    Now we need two more solutions. Since 20 works, pick numbers around 20.


Inequalities


  • Use the Guess and Check method (also called mental math) to find 3 solutions for the following inequality.


  • Can you find solutions to an inequality?

  • Go back to the classroom to get to your homework and any other items you need to attend to.