Numerical and Algebraic Expressions Jean MacIntosh From English to Math Numerical and Algebraic Expressions Jean MacIntosh Show video – You Can Learn Anything, Mind Set, Tell Standards (MP 1,2,6) PPT

Writing Math Expressions A variable is a symbol used to represent a number in an expression or an equation. The value of this number can change. An algebraic expression is a mathematical expression that consists of variables, numbers and operations. The value of this expression can change.

Example Write each phrase as a mathematical expression. Expression   Phrase Expression the sum of nine and eight the sum of nine and a number x

Example : Write each phrase as a mathematical expression. Expression   Phrase Expression the sum of nine and eight 9+8 the sum of nine and a number x 9+x

Example 2:   Write each phrase as an algebraic expression using the variable n.   Phrase Expression five more than twice a number the product of a number and 6 seven divided by twice a number    three times a number decreased by 11

Example 3: Write each phrase as an algebraic expression. Phrase   Phrase Expression nine increased by a number x 9+x fourteen decreased by a number p 14-p seven less than a number t 7-n the product of 9 and a number n 9xn thirty-two divided by a number y    32 ÷ y   or   32/y

Example 3: Write each phrase as an algebraic expression. Phrase   Phrase Expression nine increased by a number x 9 + x fourteen decreased by a number p 14 - p seven less than a number t t - 7 the product of 9 and a number n 9 · n   or   9n thirty-two divided by a number y 32 ÷ y    

Example 4: An electrician charges $45 per hour and spends $20 a day on gasoline. Write an algebraic expression to represent his earnings for one day.

Solution: Let x represent the number of hours the electrician works in one day. The electrician's earnings can be represented by the following algebraic expression: Solution: 45x - 20

Independent Practice Fifteen less than twice a number 1. 1.  Fifteen less than twice a number   O 15 - 2x O 2x + 15 O 2x - 15 O None of the above.

2. Three times a number, increased by seventeen O 3(a + 17) O 3a + 17 O (17 + 3)a O None of the above