1.2 Algebraic Expressions 8/24/12

Vocabulary Variable: A letter used to represent one or more numbers Exponent: The number or variable that represents the number of times the base of a power is used as a factor Power: An expression that represents repeated multiplication of the same factor Base: The number used as a factor in a repeated multiplication x3x3

Example 1 Evaluate Powers a = ()– b. ) 4) 4 ( 2 – ( 2 –)( 2 – ) = ( 2 –)( 2 – ) 16 = – – = What’s the difference?

ANSWER 9 64 ANSWER 2 Evaluate the power. Checkpoint ) 2) 2 ( 3 – 3.3 – ANSWER 27 – Evaluate Powers

Order of Operations Step 1: Perform operations that occur within grouping symbols. Step 2: Evaluate powers. Step 3: Perform multiplications and divisions from left to right. Step 4: Perform additions and subtractions from left to right.

Example 2 Use Order of Operations 436 ÷ ( 1 – 4+ )2)2 Add within parentheses. = 436 ÷ 3232 Evaluate power. = 436 ÷ 9 Divide. = 9 9 = 81 Multiply.

Example 3 Evaluate an Algebraic Expression Evaluate when. () 5+x27x7x – 4x = SOLUTION Substitute 4 for x. = () 5+x27x7x – () 5+42 – ( 47 ) = – ( 47 )( 92 ) Add within parentheses = Multiply. – = Subtract. 10 – Evaluate means to get a number answer after doing the math.

Example 4 Evaluate an Algebraic Expression Evaluate when. 4p24p2 – ( 2p2p ) 9 –p = 3 – = – ( 94 ) [] ( 23 – ) 9 – Evaluate power. 36 = – ( 15 – ) Subtract within parentheses. 51 = Add the opposite. 36 = Multiply. – [] 6 – 9 – SOLUTION Substitute 3 for p. = ( 4 4p24p2 – ( 2p2p ) 9 – 3 – )2)2 [] ( 23 – ) 9 – – –

– ANSWER 12 ANSWER 23 Evaluate the expression. Checkpoint 6. 2 – 62 + ÷ 4 ANSWER 8 – 7. ( 5734 –– )2)2 ANSWER 15 Evaluate the expression for the given value of the variable – + ( 1y6+ ) when 2y = Evaluate Expressions

Homework 1.2 p.12 #15-60 multiples of 3 Remember: 1.Pencil Only. 2.Write heading. 3.Copy problems and show work. 4.Circle, highlight or box final answer.