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7th Grade Math / Lesson 1: Solutions

SOLUTIONS
What will we be learning in this lesson?


  • In this lesson, you will learn about solutions of equations.
Vocabulary words are found in this purple color throughout the lesson. Remember to put these in your notebook.


A solution is a number that works for an equation. It is a number that gets substituted into the place of a variable and makes the equation work.

Look at the following equation.

2x + 5 = 21

The 2 and the x next to each other means multiplication. The x is being used as the variable, not as a multiplication symbol. Multiplication symbols will not be used as they have been. Anything being multiplied will be written next to each other as in the above equation or there will be a * between them.

The solution to this equation is the number that you can put in for the variable that gives you a 21 after completing the operations.


2x + 5 = 21

Try the number 3. Is 3 a solution to the equation?

To answer this question, you need to put the 3 into the equation.
Take the x out, and put a 3 in its place.

2*3 + 5 = 21

Now do the operations and see if the result is 21.

6 + 5 = 21
11     21

It does not equal 21, therefore, the number 3 is NOT a solution to the equation.


2x + 5 = 21

Try the number 8. Is 8 a solution to the equation?

To answer this question, you need to put the 3 into the equation.
Take the x out, and put a 3 in its place.

2*8 + 5 = 21

Now do the operations and see if the result is 21.

16 + 5 = 21
21 = 21

It DOES equal 21, therefore, the number 8 is a solution to the equation.


 This is the last page of today's lesson.


Do you know what a solution is?
Can you check or verify if a number is a solution to an equation?

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