Intro to expressions and equations
Grade Level:
Sunshine State Standard:
Materials:
· Students: Paper & pencil, balance beam (drawn on a sheet of paper will be fine), two different color chips (one to represent +1, one to represent –1).
Objectives:
· Students will be able to recognize the difference between an expression and an equation.
·
Vocabulary: Expression, equation, solution, simplify, solve, open sentence, evaluate.
Lesson Plan:
This lesson starts with some definitions of what an expression and equation is. Students will be shown different algebraic representations and be asked to decide whether they are expressions or equations.
The lesson will now turn to evaluating expressions. Students sometimes don’t realize what the word evaluate means when it comes to algebraic expressions.
Now the students will learn what it means to be an equation. Students will be shown three equations and be asked if the equations represent true or false statements. For example:
8 + 3 x 7 = 29
This equation (sentence) is true because the right side of the equation will always equal the left side of the equation.
12 /4 – 3 = -1
This equation is false because the right side of the equation will never equal the left side.
5x + 2 = 12
We cannot decide if this sentence is true or false, we need to know what the variable x has to stand for. In this case the only way the equation is true is if you replace the x with a 2.
The meaning of a solution to an equation will be discussed at this point. The students will be shown equations and be asked to mentally find the solution(s) to the equations. After some time with some mental equation solving, we try to physically model the equations and solve them that way. The powerpoint presentation “Solving one-step equations” will be used to demonstrate this to the students.
After viewing the slide show students will be asked to model their own equations and find the solutions.