Year 8: Simplification and expansion of algebraic expressions
Simplification
Simplifying means making an expression easier to understand. You do this by removing unnecessary terms and combining like terms.
Combining Like Terms
- Like Terms: Terms with the same variables and powers of those variables (e.g., 3x + 2x = 5x).
- To combine like terms, add or subtract their coefficients (the numbers in front of the variables).
- Example: 2x + 3x - x = (2 + 3 - 1)x = 4x
Expansion (or 'Multiplying Out')
Expansion means multiplying out an expression that's been written in brackets. You use the distributive property.
The Distributive Property
- a(b + c) = ab + ac
- Example 1: 2(x + 3) = 2*x + 2*3 = 2x + 6
- Example 2: 3(2x - 1) = 3*2x - 3*1 = 6x - 3
Remember to always multiply everything inside the brackets by the number outside.
Practice makes perfect: Try simplifying and expanding different expressions.