Expressions and Equations

Lesson Overview This is an interactive presentation. You will participate in 3 ways: Follow along taking notes in the handout. Respond to questions through Socrative where indicated by the symbol. I will be monitoring your responses. Discuss ideas with your partner or group when directed to do so.

Lesson Objectives Content Objectives Language Objectives Student will distinguish between an expression and an equation Student will demonstrate simplifying an expression and explain steps Student will demonstrate solving an equation and explain steps Language Objectives Student will summarize differences between expression and equation Student will explain to a partner how to simplify an expression or solve an equation

Let’s start with a puzzle Pick a number between 1 and 10 Add 3 to the number Multiply the result by 3 Subtract the original number Add 2 to the result Subtract the original number again Subtract 1 from the result What number did you end with? Enter your answer in Socrative. Then share your answer and your original number with your group. How did this happen? We’ll find out at the end of class.

Khan Academy Variables Expressions Equations

Expressions and Equations An expression is like a phrase (part of a sentence). You simplify an expression. An expression has no relation symbol. An equation is like a sentence. You solve an equation. An equation has a relation symbol. Type in an example of a relation symbol.

Expression or Equation? For each question, enter “True” if it is an equation then discuss why with your group and record it on your handout. x + 4 - 2x + 7 x - 2 = 5 9 + x - 2y + 3 2x - 10

Steps to simplify expressions and solve equations

Right and Wrong What was done right and wrong here? Talk with your group and make notes on your handout What was done right and wrong here? Talk with your group and make notes on your handout

Now your try some Show your work and write your answer on your handout. Type your answer into Socrative. 4d + 6 = 38 17 = 7x + 3 3h - 11 = 25 5t - 6 = 34 10 + 5y = 25 34 = 4p - 10

Let’s explore our puzzle Words Math Pick a number between 1 and 10 x Add 3 to the number x + 3 Multiply the result by 3 3(x + 3) Subtract the original number 3(x + 3) - x Add 2 to the result 3(x + 3) - x + 2 Subtract the original number again 3(x + 3) - x + 2 - x Subtract 1 from the result 3(x + 3) - x + 2 - x - 1 Subtract the original number again 3(x + 3) - x + 2 - x - 1 - x Using what we’ve learned about simplifying expressions, what do you get when you simplify this? 3x + 9 - x + 2 - x - 1 - x (3x - x - x - x) + (9 + 2 - 1) 0x + 10 What does this mean? No matter what x is, you always get 10