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## 7th grade (Illustrative Mathematics)

### Course: 7th grade (Illustrative Mathematics) > Unit 1

Lesson 4: Lesson 5: The size of the scale factor# Interpreting scale factors in drawings

Sal interprets a scale factor to determine if a scale copy will be larger or smaller than the original figure.

## Want to join the conversation?

- Hmmm. I see math is made up of math(31 votes)
- this makes no sense to me i feel so stupid(11 votes)
- Am I the only one who thinks this is super easy?(5 votes)
- you mean you're the only one in 3rd grade math? nah(1 vote)

- I am still unsure about the scale factor... Could you please explain it in a simpler way please? My brain is not functioning today. (¬_¬")(5 votes)
- Is that the whole video what is the right answer(3 votes)
- im so confused its crazy. i have a test tommorrow about it(3 votes)

- In the last practice theres no way to tell if you have to use whole numbers or fractions this is stupid.(3 votes)
- Actually, that is not true. You use fractions when you are scaling down, and whole numbers when scaling up.

Hope this helps!(3 votes)

- when you draw the line do you just pick how big you want it or does it have to be a certain size.(3 votes)
- i think its any size you want(2 votes)

- What is a scale factor(2 votes)
- Scale factors are like what is seen on a copy machine or on your computer. You can reduce the size of your screen by 200% (scale factor of 2) or 50% (scale factor of 1/2). Similarly, you can make copies that are smaller or larger than the original. Scale factors do just this, make something bigger or smaller than the original, but you could also still have a scale factor of 1 if you want to make a exact copy of the original.(4 votes)

- has confusion...and regrets going ahead on 6th grade(3 votes)

## Video transcript

- [Instructor] We are told
Ismael made a scaled copy of the following quadrilateral. He used a scale factor
less than one, all right. And then they say what could be the length of the side that corresponds to AD? So AD is right over here. AD has length 16 units in
our original quadrilateral. What could be the length of the side that corresponds with
AD on the scaled copy of the quadrilateral? So it's a scale factor less than one. So we're gonna get something
that is less than 16 for that side. And the rest of it will all
be scaled by the same factor. So the resulting quadrilateral
might look something, might look something like this. This is just my hand-drawn version. So the key realization is is if our scale factor is less than one, this thing right over here is going to be less than 16 units. So let's look at the choices. And it says choose three answers. So pause the video. Which of these would match if we're scaling by a
factor of less than one? Well, we just have to see which of these are less than 16 units. This is less than 16. This is less than 16. This is less than 16. And those are the only
three that are less than 16. 32 units, this would be
a scale factor of two. 64 units, this would be
a scale factor of four, clearly a scale factor
that is not less than one.