This lesson teachers the correct way to help beginning students Algebra I to learn the official Properties of Equality.[br]1) Addition Property of Equality: If [i]a = b[/i], then [i]a + c = b + c[/i][br]2) Subtraction Property of Equality: If [i]a = b[/i], then [i]a - c = b - c[/i][br]3) Multiplication Property of Equality: If [i]a = b[/i], then [i]a × c = b × c[/i][br]4) Division Property of Equality: If a = b, then a ÷ c = b ÷ c

1) Addition Property of Equality[br][b]If you add the same number to both sides of an equation, the equality remains true.[/b][br][list][*]Example: If [i]a = b[/i], then [i]a + c = b + c[/i][/*][*]Why it matters: It helps isolate variables when solving equations.[/*][/list]2) Subtraction Property of Equality[br][b]If you subtract the same number from both sides of an equation, the equality stays intact.[/b][br][list][*]Example: If [i]a = b[/i], then [i]a - c = b - c[/i][/*][*]Use case: Often used to move terms from one side to the other.[/*][/list]3) Multiplication Property of Equality[br][b]Multiplying both sides of an equation by the same number keeps the equation balanced.[/b][br][list][*]Example: If [i]a = b[/i], then [i]a × c = b × c[/i][/*][*]Important note: [i]c[/i] must not be zero when solving equations.[/*][/list]4) Division Property of Equality[br][b]Dividing both sides of an equation by the same nonzero number preserves equality.[/b][br][list][*]Example: If [i]a = b[/i], then [i]a ÷ c = b ÷ c[/i][/*][*]Key rule: Never divide by zero — it’s undefined.[/*][/list][br]