1. Agenda 1. Warm-up (10 min) 2. 3 practice problems - evaluating expressions (20 min) 3. Notes on expressions (10 min) 4. Exit slip (10 min) Warm-Up: Evaluate the following expressions when a = 2, b = 3, and c = -4 1.) a – 2c3.) a 2 + c 2 2.) 4.) SWBAT… simplify algebraic expressionsTues, 8/21 HW#1: Simplifying algebraic expressions

2. New Unit: Expressions & Equations 1. Algebraic expressions and formulas 1. Evaluating expressions (HW#5) 2. Simplifying algebraic expressions (HW#6) 1. Distributive property 2. Combining like terms 2. Linear equations in one variable 1. Solving two-step equations (HW#7) 2. Solving multi-step equations using the distributive property and combining like terms (HW#8) 3. Solving multi-step equations with variables on both sides (HW#9) 4. Solving multi-step equations involving fractions (HW#10) 5. Solving multi-step equations with no solutions or infinite solutions (HW#11) 6. Solving literal equations (HW#13) 3. Applications of linear equations (HW#12) 1. Renting a car 2. Education pays off Fundraising project at the conclusion of the unit!

3. In your own words, explain what it means to evaluate an expression. My words: To replace each letter in the expression with the assigned value.

4. Evaluating an Algebraic Expression 1.) Evaluate -x + 5(x – 4) 3 for x = 6 -6 + 5(6 – 4) 3 -6 + 5(2) 3 -6 + 5(8) -6 + 40 34 Replace x with 6 Parenthesis first: 6 – 4 = 2 Exponents: (2) 3 = (2)(2)(2) = 8 Multiply: 5(8) = 40 Add: -6 + 40 = 34 P E M/D A/S

5. Evaluating an Algebraic Expression 2.) Evaluate x 2 – 5x – 3 for x = -6 (-6) 2 – 5(-6) – 3 36 – 5(-6) – 3 36 – (-30) – 3 96 – 3 93 Replace x with -6 Exponents: (-6) 2 = (-6)(-6) = 36 Multiply: 5(-6) = -30 Subtract from left to right 36 – (-30) = 96 P E M/D A/S

6. Evaluating an Algebraic Expression 3.) Evaluate -2x 2 + 5xy – y 3 for x = 4 and y = -2 -2(4) 2 + 5(4)(-2) – (-2) 3 -2(16) + 5(4)(-2) – (-8) -32 + (-40) – (-8) -72 – (-8) -64 Replace x with 4 and y with -2 Exponents: (4) 2 = 16, (-2) 3 = -8 Mult: -2(16) = -32, 5(4)(-2) = -40 Add and subtract from left to right -32 + (-40) = -72 P E M/D A/S

7. Expressions – Vocabulary An algebraic expression consists of sums and/or products of numbers and variables.  i.e. x 3 + x 2 3xy 3 + 2xyz – 4 0.10d A term is either a single number or variable, or the product of several numbers or variables separated from another term by a + or – sign in an expression.  For example, in x 2 + 4x – 5  x 2, 4x, and -5 are all terms The variable term is the term that contains the variables. The constant term is a term that does not have a variable. The coefficient of a term is the numerical part (the number to the left of the variable)

8. Example: x 2 – 5x + 6 1. Is this an expression or equation? Expression 2. What are the terms? x 2, -5x, 6 3. What are the variable terms? x 2, -5x 4. What is the constant term? 6 5. What are the coefficients? 1, 5

9. Example: a 2 – 4a + 3 Algebraic equation or expression: Terms (separated by a + or – sign): Variable terms: Constant term: Coefficients: Warning!!! Always take the sign that is in front of the coefficient!

10. Exit Slip: 1. Simplify for x = -2 and y = 4 2. Simplify -x 2 – 3xy + 4y 3 for x = -3 and y = -1 3. Simplify 10y 2 – 1 for y = √8 (square root of 8)