2-1 Variables and Expressions Course 1 6 th Grade Math HW: Page 50 #5-17 all
2-1 Variables and Expressions Course 1 Who did not take the Chapter 1 Test?
Course 1 Warm Up Lesson Presentation Lesson Presentation Problem of the Day 2-1 Variables and Expressions Course 1
Warm Up Simplify 3 15 (9 + 2) 7 Variables and Expressions Course 1
Problem of the Day How can the digits 1 through 5 be arranged in the boxes to make the greatest product? Variables and Expressions Course 1
Today’s Learning Goal Learn to identify and evaluate expressions. 2-1 Variables and Expressions Course 1
Vocabulary variable constant algebraic expression 2-1 Variables and Expressions Course 1
A variable is a letter or symbol that represents a quantity that can change. A constant is a quantity that does not change. 2-1 Variables and Expressions Course 1
An algebraic expression contains one or more variables and may contain operation symbols. p 7 is an algebraic expression. Algebraic Expressions NOT Algebraic Expressions y 85 ÷ 5 35 w + z 5 To evaluate an algebraic expression, substitute a number for the variable and then find the value. 2-1 Variables and Expressions Course 1
Evaluate the expression to find the missing values in the table. Additional Example 1A: Evaluating Algebraic Expressions Substitute for y in 5 y. y 5 y y = 16; 5 16 = y = 27; 5 = y = 35; 5 = 2-1 Variables and Expressions Course 1 The missing values are 135 and 175.
Evaluate the expression to find the missing values in the table. Additional Example 1B: Evaluating Algebraic Expressions Substitute for z in z z z z = 20; 20 = 8 z = 45; __ = __ z = 60; __ = __ Variables and Expressions Course 1 The missing values are 13 and 16.
Try This: Example 1A Evaluate the expression to find the missing values in the table. Substitute for x in x 9. x x x = 18; 18 9 = x = 36; 9 = x = 54; 9 = Variables and Expressions Course 1 The missing values are 4 and 6.
Evaluate the expression to find the missing values in the table. Try This: Example 1B Substitute for z in 8 z + 2. z 8 z z = 7; 8 = 58 z = 9; 8 __+ 2 = __ z = 11; 8 __ + 2 = __ Variables and Expressions Course 1 The missing values are 74 and 90.
Multiplication and division can be written without using the symbols and . Instead of... You can write... x 3 x 3 35 ÷ y x(3) 3x3x 35 y When you are multiplying a number times a variable, the number is written first. Write “3x” not “x3.” Read 3x as “three x.” Writing Math 2-1 Variables and Expressions Course 1
Find an expression for the table. Additional Example 2A: Finding an Expression 39 13 = 3 n 13 = 5 52 13 = 4 n 13 An expression is n 13, or. n Variables and Expressions Course 1
Find an expression for the table. Additional Example 2B: Finding an Expression 7 4 = 28 p = = 42 7 p An expression is 7 p, or 7p. 2-1 Variables and Expressions Course 1
Find an expression for the table. 21 3 = 7 u 3 = 3 = 14 u 3 An expression is u 3, or. u 3 Try This: Example 2A 2-1 Variables and Expressions Course 1
Find an expression for the table. Try This: Example 2B 4 5 = 20 n = = 32 4 n An expression is 4 n, or 4n. 2-1 Variables and Expressions Course 1
1. Evaluate each expression to find the missing values in the tables. Lesson Quiz: Part 1 x x x – 5 2. Find an expression for the table x7x 2-1 Variables and Expressions Course 1
Lesson Quiz: Part 2 3. Evaluate 8x for x = Evaluate 4x – 1 for x = Variables and Expressions Course 1