Addition and Subtraction Equations

Addition and Subtraction Equations Created by Christine Berg Edited by V Hamilton

Inverse Operations: Addition is the opposite of subtraction and vice versa

Models = Variable = 1 = -1

Subtraction Property of Equality You can subtract the same value from both sides of an equation

Example: Arithmetic: 5 = 5 5 – 2 = 5 – 2

Example: Algebraic: If a = b then a – c = b – c

Example: x + 2 = 4 x + 2 – 2 = 4 – 2 x = 2

Example: x + 2 = 4

Example: Subtract 2 from each side

Example: x = 2

Addition Property of Equality You can add the same value to both sides of an equation

Example: Arithmetic: 9 = 9 9 + 2 = 9 + 2

Example: Algebraic: If a = b then a + c = b + c

Example: x - 2 = 4 x - 2 + 2 = 4 + 2 x = 6

Example: x - 2 = 4

Example: + + x – 2 + 2 = 4 + 2

Example: x = 6

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