About this video
Ismael makes a scaled copy of a quadrilateral using a scale factor less than one. The video shows that a scale factor less than one makes every side shorter, so the side matching AD (16 units) must be less than 16 units.
You'll be able to
- explain what a scale factor less than one does to the side lengths of a figure.
- decide which side lengths are possible in a scaled copy when I know the scale factor is less than one.
- find the scale factor that turns one length into another, such as 16 into 32.
Key words
- scaled copy
- A figure made by multiplying every length of the original by the same number.
- scale factor
- The number you multiply each length of the original by to get the copy.
- corresponding sides
- Sides that are in matching positions in the original figure and its scaled copy.
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.
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