Equations with a repeated variable

• Wiskunde
• Middelbare school
• vwo
• Leerjaar 2

Good morning!

Schedule: 

• Learning goals 
• Break
• Algebra revision
• Starter
• Equations with a repeated variable
• How many can you solve?

Learning goals 

At the end of this lessons I can:

• Solve an equation with a repeated variable
• Collect like terms
• Solve an equation by isolating the unknown

2 truths and 1 lie

Discuss with the people in your group (or row) 2 truths about the people in the group, and 1 lie.

For example: 

- everyone in this group celebrated carnival

- only 1 person in this group went on a holiday outside of the Netherland

- ..... 

1. 10x-3y
2. 7xy
3. 10xy-3xy
4. 10x​2​​−3y​2​​

1. x + 2 ÷ 3 = 21
2. (x + 2 ÷ 3) = 21
3. ​3​​x+2​​=21
4. x+​3​​2​​

1. b is a variable
2. 5 is a constant
3. 3 is a coefficient
4. 3a is a variable

1. 10(m-30n)
2. 10(m-3n)
3. 5(2m-6n)
4. 2(5m-15n)

1. x=16
2. x=3
3. x=57
4. x=27

Equations with a repeated variable 

Solve for x: 

 a).   3x - 4 + 5x = 0 

  b).    5x + 1 = 15 - 2x 

Hint: Collect all like terms 

Equations with a repeated variable 

Solve for x: 

 a).   3x - 4 + 5x = 0 

 x = 

  b).    5x + 1 = 15 - 2x 

x = 2

Hint: Collect all like terms 

​2​​1​​

5 minute challenge

Homework

MyiMaths: Equations 3 - both sides 

Scavenger hunt!

- start at a random picture and write down which picture it is. 

- solve the equation and write down the value of the unknown/variable

- find this value with the next picture

- you have finished when you arrive at the picture where you started