Algebra Revision

Note 1: Substitution Substitution means replacing a symbol with a value. Remember to follow the rules of BEDMAS. Examples: Calculate the value of these expressions 7x – 1 when x = 2 7  2 – 1 = 14 – 1 = 13

when f = 2 and g = 6 = 4 5x2 - 3x + 2 when x = -3 5  (-3)2 - 3  -3 + 2 = 56

Note 2: Solving Equations To solve equations you must: Get the unknown to one side of the equal sign by itself Do the same operation to both sides of the equation Start each step on a new line with all the equals signs lined up In an equation with more than one operation, the opposite operations must be applied in reverse order

Examples: Solve = 7 6x + 5 = 17 - 3 = 9 6x = 17 - 5 x + 3 = 7 x 2   Examples: Solve = 7 6x + 5 = 17 - 3 = 9 6x = 17 - 5 x + 3 = 7 x 2 = 9 + 3 6x = 12 x + 3 = 14 x = 2 x = 14 - 3 = 12 x = 11 x = 12 x 5 x = 60

Worksheets: Substitution Solving Eqns