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Solve Equations with Variables on One Side
Teacher Notes
Still use algebra tiles!Still use algebra tiles!Students write and solve equations from word problems. . Supplies Each student needs a bag of algebra tiles.
7/14/11
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Target 3a I can write an equation to solve a problem.
What do you think this means?
Can you give an example?
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LaunchLaunchLaunchLaunchSolve. Remember from last year. • 3x = 6
• 2x + 1 = 7
Be prepared to share your
work…
Be prepared to share your
work…
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The left side of an equation is equal to the right side.
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The left side of an equation is equal to the right side.
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The left side of an equation is equal to the right side.
25¢ 25¢ =
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Get a piece of blank paper
• Fold it in half hamburger style.• Use the fold to divide the 2 sides of
the equation.
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Use Algebra Tiles to Solve
Cindy, my sister, read two more books than me. She read 5 books. How many did I read?
What are you asked to find?Define x: Write an equation to solve
the problem.
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Cindy, my sister, read two more books than me. She read 5 books.
How many did I read?
Books I read. Books Cindy read.
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Cindy, my sister, read two more books than me. She read 5 books.
How many did I read?
Keep it balanced.Do exactly the same to both sides of the equation.
Books I read. Books Cindy read.
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What did I just do?Did I keep it balanced?
Cindy, my sister, read two more books than me. She read 5 books.
How many did I read?
Books I read. Books Cindy read.
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13What is the solution?
I read 3 books.
Cindy, my sister, read two more books than me. She read 5 books.
How many did I read?
Books I read. Books Cindy read.
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I used 3 one-dollar bills when I bought lunch. After lunch, I had 1 one-dollar left in my wallet. How many one-dollar bills did I have before lunch?
What are you asked to find?Define x: Write an equation to solve the
problem.
Use Algebra Tiles to Solve
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I used 3 one-dollar bills when I bought lunch. After lunch, I had 1 one-dollar left in my wallet.
How many one-dollar bills did I have before lunch?
How can I get x alone and still keep the equation balanced?
Remove zero pairs
Remove zero pairs
Before lunch
After lunch
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I had $4 before lunch.
I used 3 one-dollar bills when I bought lunch. After lunch, I had 1 one-dollar left in my wallet.
How many one-dollar bills did I have before lunch?
Before lunch
After lunch
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Check it: x = 4 x + (-3) = 1
1 1 =
:-)
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John has 4 video games. He has a goal to buy 3 each month until he has 10 games. How many months does he need to buy games to reach his goal?
What are you asked to find?Define x: Write an equation to solve the problem.
Use Algebra Tiles to Solve
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John has 4 video games. He has a goal to buy 3 each month until he has 10 games. How many months does he need to buy games to reach his
goal?John’s Games
John’s Goal
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John has 4 video games. He has a goal to buy 3 each month until he has 10 games. How many months does he need to buy games to reach his
goal?John’s Games
John’s Goal
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John has 4 video games. He has a goal to buy 3 each month until he has 10 games. How many months does he need to buy games to reach his
goal?John’s Games
John’s Goal
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John has 4 video games. He has a goal to buy 3 each month until he has 10 games. How many months does he need to buy games to reach his
goal?John’s Games
John’s Goal
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How can we solve for 1x?
John has 4 video games. He has a goal to buy 3 each month until he has 10 games. How many months does he need to buy games to reach his
goal?John’s Games
John’s Goal
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John has 4 video games. He has a goal to buy 3 each month until he has 10 games. How many months does he need to buy games to reach his
goal?John’s Games
John’s Goal
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John has 4 video games. He has a goal to buy 3 each month until he has 10 games. How many months does he need to buy games to reach his
goal?John’s Games
John’s Goal
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John buys games for 2 months.
=
John has 4 video games. He has a goal to buy 3 each month until he has 10 games. How many months does he need to buy games to reach his
goal?John’s Games
John’s Goal
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Check it: x = 23x + 4 = 10
10 10=
:-)
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Debrief
Write what you know about using algebra tiles to solve a problem.
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5
3
12
4
Did you hit the target?Target 3a I can write an
equation to solve a problem.
Rate your understanding of the target from 1 to 5.
5 is a bullseye!
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PracticePractice
Practice 2.5____
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Ticket Out
Solve with algebra tiles.Lizzy bought 4 pens with a $10 bill and
got $2 in change. What was the average she spent on each pen?
What are you asked to find?Define x: Write an equation to solve the problem.