6th Grade Math Textbook, Fundamentals

Write an equation for each. Label each equation as numericalor algebraic.

1.Six less than the absolute value of a 2.Four times negative five is equal to

number is equal to twelve. negative twenty.

3.One more than twice the opposite of a 4.A number divided by 7 is 21.

number is equal to six.

5.Toni is 3 feet tall. She is half the height

of her father.

Identify whether the equation is an openor closedsentence.

6.n 8  9 7.  5  10 8.x^2  14

Determine whether the given value for the variable is a solution of the
equation. Write trueor false. Show the steps to support your conclusion.

9. 3 x18 when x 6 10. 53  26 ywhen y 25 11. |18 | when z= 2

12.Discuss and WriteWrite two word sentences for the equation 2x 4 24.

20

4

 36

z

42 4 20 Substitute 4 for x.

16  420 Simplify.

20  20 Tr u e

4 is a solution of the equation.

(5)^2 4 20 Substitute 5 for x.

25 4 20 Simplify.

29  20

5 is not a solution of the equation.

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6 4 10

10  10

So 6  4 10 is true.

6 5 12

11  12

So 6  5 12 is false.

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Lesson 2-3 for exercise sets. &KDSWHU 

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An equation can be a closed sentenceor an open sentence.

• A is a numerical statement. It does notcontain
  variables. Closed sentences are either true or false.

closed sentence

• An is an algebraic statement. It doescontain one
  or more variables. Open sentences are neither true nor false.

a 2 7 is an open sentence.

open sentence

You can determine whether a given value for a variable is a solution

of an equation. A is a value for the variable that makes an

algebraic equation true. An algebraic equation may have more than

one solution.

Determine whether x4 and x5 are solutions

of the equation x^2  4 20.

solution

means “is not equal to.”