Algebra I in Simple English/Solving Equations/Solving Equations with Variables on Both Sides of the Equation

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(Note to contributors: Please use the ^ symbol to designate exponents when you enter them in the wikibook. I will format them on the student-user interface.--HSTutorials 00:42, 17 July 2006 (UTC)

Contents

[edit] Vocabulary

Variable - a letter (A-Z) that takes the place of a number.

Equation - an example would be: 8y - 3 = 1 + 10y (The answer is -2 [negative two] = y)

[edit] Lesson

NOTE: WHAT YOU DO TO ONE SIDE YOU MUST DO TO THE OTHER! NO EXCEPTIONS!

1) do the distributive property.

2) Combine like terms on both sides.

3) add/subtract numbers next to a variable on both sides.

4) divide by the number next to the variable on both sides.

5) The answer should look like: x=20 or 20=x

(Note: the variables and numbers may vary in your answer.)

[edit] Example Problems

A simple problem:


2(x + 5) = 5(x − 10)<---Problem

2x + 10 = 5x − 50<---Distributive Prop.

2x + 10 − 2x = 5x − 2x − 50<---Subtract the variables with numbers next to them.

10 = 3x − 50<---This is what you're left with.

10 + 50 = 3x − 50 + 50<---get rid of the 50 by subtracting

60 = 3x<---This is what you're left with.

60 / 3 = 3x / 3<---Get rid of the three by dividing by three

20 = x<---This is your answer.

[edit] Practice Games

Put links here to games that reinforce these skills

Purplemath.com: http://www.purplemath.com/modules/index.htm

[edit] Practice Problems

(Note: put answer in parentheses after each problem you write)

Practice Problem #1:

3v - 2 = v + 16 {v = 9}

Practice Problem #2:

2x = 15 - x {x = 5}

Practice Problem #3:

([z - 5] / -3) = 9 + 3.4z {z = -1.96}