3­1 Notes: The Distributive Property 1 E.g. Use the distributive property to write each expression as an equivalent expression. Then evaluate the expression. 1) 4(5+8) 2) (6+9)2 2 3 E.g. Use the distributive property to write each expression as an equivalent algebraic expression. 3) 2(x+4) 4) (y+3)6 5) ­2(n­3) 4 3­1 CW 5 3­1 Reflection I feel that I can use the distributive property... because... I feel that one thing that helps me to simplify expressions is... 6 3­2 Notes: Simplifying Algebraic Expressions like terms 3x ­ 4x +term y ­2 coefficient constant 7 e.g. Identify the terms, like terms, coefficients, and constants in each expression. 1) 4x + 3 + 5x + y 8 e.g. Simplify each expression. 1) 5x + 4x 2) 8n + 4 + 4n 3) 6x + 4 ­ 5x ­ 7 4) ­y +2(x + 3y) 9 3­2 CW 10 11 3­2 Reflection List three vocabulary terms from this section and give an example of each. Write a checklist of things to look for when simplifying expressions I can grow in this area by... 12 3­3 Notes: Solving Equations by Adding or Subtracting The subtraction property of equality 5=5 5­3 = 5­3 2=2 The addition property of equality 5=5 5+3 = 5+3 8=8 13 Inverse Operation = Undo what is being done to the variable to solve Equivalent Equations have the same solution 14 E.g. Solve. 1) x + 4 = ­3 2) y ­ 3 = ­14 15 E.g. Graph the solution on a number line 1) x + 8 = 7 16 3­3 CW 17 3­3 Reflection Explain the subtraction property of equality in your own words. Explain the addition property of equality in your own words. 18 3­4 Notes: Solving Equations by Multiplying or Dividing The division property of equality 6=6 6/3 = 6/3 2=2 The multiplication property of equality 6=6 6X3 = 6X3 18 = 18 19 20 To solve remember to "undo" whatever is happening to the variable in the equation. • Addition and Subtraction are inverse operations • Multiplication and Division are inverse operations 21 E.g. Solve each equation. Check your solution. 1) 7x = ­56 2) y = ­12 ­5 22 3) 8a = ­48 4)­3b = 27 5) 12c = ­48 23 6) k = 9 3 7) ­11 = n ­6 24 E.g Esteban spent $112 on boxes of baseball cards. If he paid $14 per box, how many boxes of cards did Esteban buy? 25 3­4 CW 26 3­4 Reflection Pretend that your neighbor was absent for sections 3 and 4 from this chapter. Explain to them how to solve an equation. Use words and give an example. 27 3­5 Notes: Solving Two­Step Equations To solve: 1) simplify (combine like terms) 2) get constants on only 1 side of the equation 3) get rid of the coefficient Remember­the goal is to have the variable all alone on one side of the equation. 28 E.g. Solve. Check your solution. 1) 3x ­ 4 = 17 2) 3 = n + 8 7 29 3) 5 ­ x = 7 4) b ­ 3b + 8 = 18 30 5) 3y + 4 = 13 Show work­help your group 6) 20 ­ z = 11 7) 3n + n ­4 = 12 Show work­help your group 31 3­5 CW 32 3­5 Reflection Explain, using words, how to solve a two­step equation. 33 3­6 Notes: Writing Two­Step Equations Assign a variable to the unknown. 34 E.g. translate each sentence into an equation. 1) Twice a number, increased by 5 equals ­25. answer: 2n + 5 = ­25 2) Four times a number minus 8 equals 28. answer: 4n ­ 8 = 28 35 3) When five is added to the product of a number and 8, the result is 12. answer: 5 + 8n = 12 36 E.g. 1) Nine more than four times a number is 41. Find the number. answer: 9 + 4n = 41 ­9 ­9 4n = 32 4 4 n = 8 37 3­6 CW 3­6 CW 38 3­6 Reflection I feel that writing down equations from words is... Copy the following: 39 3­7 Notes: Using Formulas A formula is an equation that shows a relationship among certain quantities. A formula usually contains two or more variables. 40 Some formulas: 41 E.g. If you travel 135 miles in 3 hours, what is your average speed in miles per hour? 42 E.g. Find the perimeter of the rectangle. 15 cm 20 cm 43 E.g. Find the area of a rectangle with length 14 feet and width 6 feet. 44 E.g. The area of a rectangle is 40 square meters. Its length is 8 meters. Find its width. 45 3­7 CW 1) Find the perimeter and area of a rectangle that is 3 cm wide and 7 cm long. 2) Find the length of a rectangle that is 5 cm wide and has an area of 20 cm2. 46 3­7 Reflection The difference between area and perimeter is... When I use a formula I need to be sure to... 47 Review Reflection • The type of problem in this chapter that is the most challenging for me is... • The type of problem that is easiest for me in this chapter is... • I will ... to be ready for the test. • I need to ... to prepare my math binder for tomorrow. 48 49