logging in or signing up Lesson 1.1 - Using Variables freylerl Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: Embed: Flash iPad Dynamic Copy Does not support media & animations Automatically changes to Flash or non-Flash embed WordPress Embed Customize Embed URL: Copy Thumbnail: Copy The presentation is successfully added In Your Favorites. Views: 804 Category: Education License: All Rights Reserved Like it (1) Dislike it (0) Added: July 09, 2009 This Presentation is Public Favorites: 3 Presentation Description No description available. Comments Posting comment... By: cchoura (52 month(s) ago) Good presentation. Is it able to be downloaded? Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript 1.1 Using Variables : 1.1 Using Variables Vocabulary : Vocabulary A variable represents a number that can have many values. Variables represent numbers that can vary Generally, letters are used as variables An algebraic expression is a phrase that can include numbers, variables and operation symbols. n – 7 x2 + 8 An equation is a math sentence that uses an equal sign. y ? 5 = 20 An open sentence is an equation that contains one or more variables. k + m = 14 Operation Terms : Operation Terms Sum: Addition, + More than, plus Difference: Subtraction, – Less than, less, minus Product: Multiplication, ? times Quotient: Division, ? , ? Divided by 1. Writing Algebraic Expressions : 1. Writing Algebraic Expressions the sum of n and 8 the sum of n and 8 n + 8 Because addition is commutative, order doesn’t matter six less than b six less than b 6 – b b – 6 Because subtraction is not commutative, order does matter c) the product of 7 and n the product of 7 and n 7 ? n 7n Because multiplication is commutative, order doesn’t matter. d) the quotient of n and 8 the quotient of n and 8 n ? 8 Because division is not commutative, order does matter. 2. Define a Variable & Write an Algebraic Expression : 2. Define a Variable & Write an Algebraic Expression ten more than twice a number ten more than twice a number Let n = a number 10 + 2n three times a number minus six three times a number minus six Let b = a number 3 ? b – 6 3b – 6 c) four less than a number divided by eight four less than a number divided by eight Let y = a number 4 – y ? 8 d) the product of one half a number and twelve the product of one half a number and twelve Let a = a number ½ a ?12 12 ? ½ a 6a (remember, with multiplication, order doesn’t matter) 3. Write an Equation : 3. Write an Equation a) The total income from selling tickets to a school play for $5 each. RELATE: total income is 5 times the # of tickets sold What does ‘is’ mean in mathematical terms? DEFINE: Let t = total income Let s = # of tickets sold EQUATION: t = 5 ? s t = 5s 3. Write an Equation : 3. Write an Equation b) the perimeter of a regular hexagon is 6 times the length of one side RELATE: the perimeter is 6 times the length of one side DEFINE: Let p = perimeter Let s = length of one side EQUATION: p = 6 ? s p = 6s 4. Write an Equation : 4. Write an Equation RELATE: How are the numbers in each pair related to one another? the # of miles traveled is 20 times the # of gallons used the # of miles traveled is 20 times the # of gallons used How else could we say these two sets are related to each other? DEFINE: Let m = the # of miles traveled Let g = the # of gallons used EQUATION: m = 20g You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.