About this video
Sal finds the translation that moves a blue shape onto an orange dashed shape by tracking a single point. The point moves one unit left and one unit down, which is written as -1 horizontally and -1 vertically.
You'll be able to
- describe a translation by following what happens to one point.
- write left/right and up/down moves as negative or positive numbers.
Key words
- translation
- A slide that moves every point of a shape the same distance in the same direction.
- horizontal
- Left-right direction; moving left is negative, right is positive.
- vertical
- Up-down direction; moving down is negative, up is positive.
Transcript
PROBLEM: What was the translation applied to move the blue solid shape to the orange dashed shape? So if you were to start with this blue solid shape, and you wanted to shift it to where the orange dotted shape is, how would you do that? And the way that I like to think about it is to just pick a point, and see what had to happen to that point.
So this point at the top of this – I guess – this quadrilateral-looking thing, it moved down here. So it moved one to the left. And it moved one down. So we can denote that with a transformation. Moving one to the left is negative one (-1) in the horizontal direction.
If we were moving to the right, it would have been a positive one (+1). And we moved one down, in the vertical direction. And that is another negative one (-1).
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