Using Algebra Tiles to Combine Like Terms OBJECTIVE

Using Algebra Tiles to Combine Like Terms OBJECTIVE: TO UNDERSTAND THE DIFFERENT PARTS OF AN EQUATION, AND USE ALGEBRA TILES TO HELP US SOLVE PROBLEMS.

Important Vocabulary! • Equation – An equation is a mathematical statement that uses an equal sign to show that two expressions have the same value. • To solve an equation that contains a variable, find the value of the variable that makes the equation true. This value of the variable is called the solution of the equation. • Term – the parts of an expression that are added or subtracted. • Like Term – Two or more terms that have the same variable raised to the same power. • Coefficient – The number that is multiplied by a variable in an algebraic expression. • Constant – A value that does not change. • Equivalent Expression – Equivalent expressions have the same value for all values of the variables.

Parts of an Expression! Like Terms 5 x + 4 x + 5 constant coefficient variable

Your Turn… 6 y + 5 x + 2 y = 42 • Coefficients? • Variables? • Like Terms? • Constant?

Discovery • What do you think the different tiles stand for? Why?

Algebra Tiles What do these stand for? Why?

Let’s Try It • Represent the following equations on your tile mat. Compare your answer with a neighbor. Assist each other as needed. 5+x=2 5 – 5 x = -1 2 x – 5 = 9

Combining Like Terms What does this tile represent? x 2 -x 2 What does this tile represent? What do these tiles represent? x -x 1 -1

Combining Like Terms 4 x + 5 These are NOT the same shape Can these be combined? Explain your reasoning. 4 x + 5 x Can these be added together? Explain your reasoning.

Let’s Try It! Represent the following expressions on your tile mat. Compare your answer with a neighbor. Assist each other as needed. 3 x + 4 – 2 x 3 x + 5 2 x 2 – 6 x +2 x 2 – 2 x – 3 3 x 2 + 3 x – 5 x

Combining Like Terms: Build It! 2 x 2 + 3 x + 5 +x 2 – 5 x – 1 x 2 x x x 1 1 1 Try these: -1 2 x 2+4 x+2 x 2 – x 3 x 2 – 2 x – 1 – 3 x 2 – 2 x – 2 x 2+2 x+1 – 3 x 2 – x 3 x 2 – 3 x + x 2 – 1 + 2 x – 3 x 2 -x -x -x

Combining Like Terms: Build It! 2 x 2 + 3 x + 5 +x 2 – 5 x – 1 x 2 x x x 1 1 1 Try these: -1 2 x 2+4 x+2 x 2 – x 3 x 2 – 2 x – 1 – 3 x 2 – 2 x – 2 x 2+2 x+1 – 3 x 2 – x 3 x 2 – 3 x + x 2 – 1 + 2 x – 3 What’s left? ? -x -x -x

Summary • Write 2 – 3 sentences explaining how you use algebra tiles to combine like terms. Pretend you are teaching this concept to a 4 th grader.