DB1N 16-6

• Wiskunde
• Middelbare school
• vwo
• Leerjaar 1

Welcome

Planning

• Prior knowledge
• New theory

Grab your laptop

Simplify

10a⋅−2b

1. 20ab
2. 12ab
3. -20ab
4. 8a

Simplify

7xy+8xy

1. xy
2. 14xy
3. 14x
4. 15xy

Simplify

−3ab+7ac

1. 4ab
2. na
3. 4bc
4. 4ac

Simplify

3a⋅6a

1. 18a​2​​
2. 18a
3. na
4. 9a

Simplify

−4x⋅−7y

1. -28xy
2. 28xy
3. na
4. -11xy

Put your laptop away and grab your notebook

New theory

You saw how to simplify products with letters and how to simplify like terms.

Now we are going to combine these two. 

How would you calculate 

3⋅8+7⋅5

How would you calculate 

3⋅8+7⋅5

3⋅8+7⋅5=

How would you calculate 

3⋅8+7⋅5

first multiplication

3⋅8+7⋅5=

3⋅8+7⋅5

How would you calculate 

3⋅8+7⋅5

24+35=

first multiplication

3⋅8+7⋅5=

3⋅8+7⋅5

How would you calculate 

3⋅8+7⋅5

24+35=

first multiplication

3⋅8+7⋅5=

then the sum

3⋅8+7⋅5

How would you calculate 

3⋅8+7⋅5

24+35=

first multiplication

59

3⋅8+7⋅5=

then the sum

3⋅8+7⋅5

But what when there are letters in the calculation?

5⋅3a+6⋅4a

But what when there are letters in the calculation?

5⋅3a+6⋅4a

What do you think is the first step?

But what when there are letters in the calculation?

5⋅3a+6⋅4a=

Step 1: multiplication

Write down!

But what when there are letters in the calculation?

5⋅3a+6⋅4a=

Step 1: multiplication

Write down!

15a+24a=

But what when there are letters in the calculation?

5⋅3a+6⋅4a=

Step 1: multiplication

Write down!

15a+24a=

What is the next step?

But what when there are letters in the calculation?

5⋅3a+6⋅4a=

Step 1: multiplication

Step 2: combine like terms

Write down!

15a+24a=

But what when there are letters in the calculation?

5⋅3a+6⋅4a=

Step 1: multiplication

Step 2: combine like terms

Write down!

15a+24a=

39a

Simplify                          

2⋅9b−3b⋅3

Write down the intermediate steps!

How to simplify                             

6x⋅5y+3y⋅z

6x⋅5y+3y⋅z=

Step 1:

Write down

How to simplify                             

6x⋅5y+3y⋅z

6x⋅5y+3y⋅z=

Step 1: multiplication

Write down

How to simplify                             

6x⋅5y+3y⋅z

6x⋅5y+3y⋅z=

Step 1: multiplication

36xy+3yz=

Write down

How to simplify                             

6x⋅5y+3y⋅z

6x⋅5y+3y⋅z=

Step 1: multiplication

Step 2: 

36xy+3yz=

Write down

How to simplify                             

6x⋅5y+3y⋅z

6x⋅5y+3y⋅z=

Step 1: multiplication

Step 2: combine like terms

36xy+3yz=

Write down

How to simplify                             

6x⋅5y+3y⋅z

6x⋅5y+3y⋅z=

Step 1: multiplication

Step 2: combine like terms

36xy+3yz

Write down

Simplify                          

6a⋅7b−4b⋅5c

Write down the intermediate steps!

Questions?

Homework:

For Monday 21 June

Make: ex. 5, 7, 8, 10 on page 93