Translating Algebraic Expressions From “English” to “Math”

Objective The student will be able to: translate verbal expressions into math expressions and vice versa.

What is the area of a rectangle? Length times Width If the length is 3 meters and the width is 2 meters, what is the area? A = L x W A = 3 x 2 = 6 meters2 A, L and W are the variables. It is any letter that represents an unknown number.

An algebraic expression contains: 1) one or more numbers or variables, and 2) one or more arithmetic operations. Examples: x - 3 3 • 2n

In expressions, there are many different ways to write multiplication. 1) ab 2) a • b 3) a(b) or (a)b 4) (a)(b) 5) a x b We are not going to use the multiplication symbol any more. Why?

Division, on the other hand, is written as: 1) 2) x ÷ 3

Throughout this year, you will hear many words that mean addition, subtraction, multiplication, and division. Complete the table with as many as you know.

Here are some phrases you may have listed. The terms with Here are some phrases you may have listed. The terms with * are ones that are often used.

Write an algebraic expression for 1) m increased by 5. 2) 7 times the product of x and t. 7xt or 7(x)(t) or 7 • x • t

3) 11 less than 4 times a number. 4) two more than 6 times a number. 6n + 2 5) the quotient of a number and 12.

Which of the following expressions represents 7 times a number decreased by 13? Answer Now

Which one of the following expressions represents 28 less than three times a number? Answer Now

Write a verbal expression for: 1) 8 + a. The sum of 8 and a 2) The ratio of m to r Do you have a different way of writing these?

Which of the following verbal expressions represents 2x + 9? 9 increased by twice a number a number increased by nine twice a number decreased by 9 9 less than twice a number Answer Now

Which of the following expressions represents the sum of 16 and five times a number? Answer Now

Your Turn You will record your partner work on a paper that will be turned in. Please fold your paper into 6 boxes. For the first part of this partner work, you will work with 1 partner at a time. You will move about the class switching partners to “play” more than once

Guess my number (Part 1) You will think of a number You will add/subtract/multiply/divide it by another number Repeat step 2 You will find the end result You will tell your partner what you did, but not what you started with… They will have to figure that out!!!

Questions to Guide your Thinking What operations ( +, - , × , ÷ ) are used? What order are they used in? What are the opposite of the operations… aka the inverse operations? What is the reverse order? In order to find the original number, you have to do the INVERSE in REVERSE!!!

Individual Practice Complete the worksheet Copy the problem Show all of your work in each box

Guess My Number (Part 2) This requires 3 person groups You will determine your partners’ numbers by using sum and difference Partner 1 and 2 will determine the difference between their numbers, and the sum of their numbers and tell that info to Partner 3 Partner 3 will determine the two numbers