How do you write equivalent expressions with variables?
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Transcript of How do you write equivalent expressions with variables?
How do you write equivalent expressions with variables?
For example, how can you write an equivalent expression for 3x2 + 4x + 3?
In this lesson you will learn how to write equivalent
expressions with variables by using a visual/area model.
Let’s ReviewLet’s Review
We know that algebraic expressions contain numbers, operations and at
least one variable.
2(x + 3)
4a-3 15 ÷ y
12 - w2
Let’s ReviewLet’s ReviewThe Distributive Property lets you
multiply a sum by multiplying each addend separately and then add the
products.
3(2 + 4) = (3 x 2) + (3 x 4)
Let’s ReviewA Common Mistake
Combining x2 and x terms.
Let’s ReviewCore LessonWhat does an algebraic expression look
like?Let:
Stand for 1
Stand for x Stand for x2
Let’s ReviewCore LessonWe can show that the blue square
represents x2 because
x
x
x2
Let’s ReviewCore Lesson
3x2 + 4x + 3
How could you regroup these to make an equivalent expression?
Let’s ReviewCore Lesson
x2 x2 x2 x x x x 1 1 1
3 x2 + 4x + 3 is equivalent to x2 + x2 + x2 + x + x + x + x + 1 +
1 + 1
Let’s ReviewCore Lesson Regroup
2x2 + x2 + 2x + 2x + 3 is another way to write an equivalent
expression for 3x2 + 4x + 3.
2x2 x2 2x 2x 3
Let’s ReviewCore LessonLet’s find two equivalent expressions for
3(x + 1)The Distributive Property can help us.
3(x + 1) = (3 • x) + (3 • 1) = 3x + 3 That’s one!
Let’s ReviewCore LessonLet’s use the first equivalent expression to
write another.3x + 3
A drawing can help us.We can regroup these.
2x + x
+ 3
In this lesson you have learned how to write equivalent
expressions with variables by using a visual/area model.
Let’s ReviewGuided PracticeUsing a drawing, write an equivalent expression for 2x2 + 2x + 2 .
Let’s ReviewExtension Activities
Use drawings and the Distributive Property to help you determine which of these expressions pairs is equivalent: 4x2 + 12 and 4(x2 + 3) 2y +1 and 2(y + 1)
Let’s ReviewExtension Activities
Use a drawing and the Distributive Property to help you write an equivalent expression for a. 2(2x + 3) b. 3x2 + 3x + 3 …
Let’s ReviewExtension Activities
Write two equivalent expressions for x2 + 2x + 6.
Let’s ReviewQuick Quiz
Write an equivalent expression for 2x2 + x + 4
Let’s ReviewQuick Quiz
Write an equivalent expression for 2(x + 1).