RULES FOR ADDITION • Put the two sets of expressions on top of each other to add like terms • Simplify
Ex. 1) Simplify. (8 x + 3) + (-6 x + -2) Rewrite vertically with like terms in columns. Solve the columns. 8 x + 3 + -6 x + -2 2 x + 1
Ex. 2) Simplify. Rewrite vertically with like terms in columns. Solve the columns. (-5 x – 9) + (6 x + 1) -5 x – 9 + 6 x + 1 = 1 x – 8
RULES FOR SUBTRACTION • The subtraction sign in front of an expression in parentheses means that you will have to “distribute” the negative to everything inside. • We can rewrite the problem: – Change the minus sign to a plus sign – Change all of the #s inside the parentheses to their opposites
Ex. 1) Simplify. Rewrite as adding the opposite. Rewrite vertically with like terms in columns. Solve the columns. (8 x + 3) – (6 x + 2) (8 x + 3) + (-6 x + -2) 8 x + 3 + -6 x + -2 2 x + 1
Ex. 2) Simplify. Rewrite as adding the opposite. Rewrite vertically with like terms in columns. Solve the columns. (-6 x + 1) – (2 x – 5) (-6 x + 1) + (-2 x + 5) -6 x + 1 + -2 x + 5 -8 x + 6
Ex. 3) Subtract (-2 x + 5) from (-4 x – 7). Be careful with order as you set up the subtraction problem! Rewrite as adding the opposite. Rewrite vertically with like terms in columns. Solve the columns. (-4 x – 7) – (-2 x + 5) (-4 x – 7) + (+2 x + -5) -4 x + -7 + 2 x + -5 = -2 x – 12
Ex. 4) Simplify. Rewrite as adding the opposite. Rewrite vertically with like terms in columns. Solve the columns.