Year 9: Simplification and expansion of algebraic expressions

Rules for simplification

  • Like terms: Terms with the same variables and powers added or subtracted together. Example: 3x+2x=5x
  • Distribute: When multiplying a number outside a bracket by terms inside the bracket. Example: 2(x+3)=2x + 6
  • Remove brackets: Use the distributive property.

Rules for expansion

  • The Product Rule:a(b+c)=ab+ac
  • Multiplying Variables: Multiply all variables together.

Examples

Example 1 (Simplification):3x+4y+2x-y=(3x+2x)+(4y-y)=5x+3y

Example 2 (Expansion):2(x+3)=2x+6

Example 3 (Expansion):3(2x+4y)=6x+12y