Challenge Your Brain with Algebra Developed by Ivan Seneviratne

Collecting Like Terms Example: 2a + 3a = 5a m + 8 + m = 2 m + 8 One of the most common ways to simplify an expression is to combine like terms. Numeric terms may be combined, and any terms with the same variable part may be combined. Example: 2a + 3a = 5a m + 8 + m = 2 m + 8

Simplify 2x² - 3xy + 2yx + 3y² = 2x² - 3xy + 2xy + 3y² The two middle terms are like terms because xy = yx, so: 2x² - 3xy + 2yx + 3y² = 2x² - 3xy + 2xy + 3y² = 2x² - xy + 3y²

Work out 5a - 2a + 4a - 6a 5b - 4b - 8b + 2b

Substitution m + 8 = 2 + 8 = 10 r – 3 = 5 – 3 = 2 Substitution is to find the value of an algebraic expression by substituting numbers for variables. Example: Find the value of the expression when m = 2 m + 8 = 2 + 8 = 10 Find the value of the expression when r = 5 r – 3 = 5 – 3 = 2

Your Turn x + 8 18 x + 49 x + x 59 x – x x – 7 20 42 - x 3 32 Evaluate each algebraic expression when x = 10 x + 8 x + 49 x + x x – x x – 7 42 - x 18 59 20 3 32

Challenge # 1 Can the expression 2x and x + 2 ever have the same value? If so, what must be the value for x.

This presentation is developed by Ivan Seneviratne © 2006 purely for personal use. ivanthexplorer@yahoo.co.uk