1. Please have out notebook, pencil, white board marker Warm-up Translate the following into algebraic expressions 1.Eleven more than a number divided by 3. 2.Three increased by 12 times a number. 3.3 times the difference of a number and 12. 4.Half of a number plus 3. Remember to write out obj & prof & level

2. Answers to warm-up 1.11 + x / 3 2.3 + 12x 3.3(x-12) 4.x/2 + 3 OBJ: TO write alg expressions using # & variables & to use the order of operations

3. 1.1 numbers & operations 4 Basic operations: 1.Addition: sum, added to, plus, increased by 2.Division: half of, quotient, divided by, split into 3.Subtraction: less, minus, decreased by, subtract, difference, taken away 4.Multiplication: times, product, doubled, multiplied by

4. 1.2 Variables in Expressions Variable: a letter used to represent a number Value of the variable: the number the variable represents Algebraic expression: a collection of numbers, variables, operations, & grouping symbols. Evaluating an expression: solving the expression by inputting a number in for the variable(s)

5. Algebraic expression 8y 16a/b 4r + 2 Meaning 8 times y 16 times a then divide by b 4 times r then plus 2

6. Brain Break You have 10 seconds to get up & change seats w/someone across the room

7. 3 simple steps to help you evaluate expressions correctly 1.Write the algebra expression4x 2.Substitute values for the variable(s). x = 2 4(2) 3.Simplify the numerical expression8

8. examples 5x + 4y, when x = 3 and y = 2 5x + 4ywrite the expression 5(3) + 4(2)substitute the #s 15 + 8 = 23simplify X + (2x -1) when x = 3 X + (2x -1)write the expression 3 + (2*3 – 1)substitute the # 3 + (6 – 1)simplify 3 + 5 = 8simplify

9. Algebraic equations used in real life Area of a rectangle A = LW If L = 4 cm and W = 14 cm, what is the area? A = 56 cm 2 Distance distance = rate(time) d = rt If a car travels 15 mph for 4 hours, how far did the car travel? D = 60 miles

10. White boards out

11. Try these 1. x – 9 when x = 21 2.xy when x = 3 and y = 2 3.Distance d = rt Rate = 60 mphtime = 2 hrs. 4.Area of a rectangle Answers 1)12 2)6 3)D = 120 Miles 4)A = 12 in 2 2 in. 6 in.

12. Any questions Homework Pg. 5 #15-23 odds Pg. 11-12 #7-19 odds