About this video
Sal uses the translation tool to find the translation that maps triangle WIN onto a target triangle. Point W must go from x = 2 to x = -5, a change of -7, and down 4 units, so the translation moves every point 7 left and 4 down.
You'll be able to
- find a translation by comparing a point with its matching point in the image.
- find the change in x and the change in y, including negative changes.
- describe a translation as an x change and a y change, like -7 and -4.
Key words
- Translation
- Moving every point of a shape the same amount in the same direction.
- Map onto
- Move one shape so it lands exactly on top of another.
- Corresponding point
- The point in the image that matches a point in the original shape.
Transcript
- [Voiceover] We're asked to use the translation tool to determine the translation that will map triangle WIN, so this right over here, onto the other triangle. So let's see if we can translate this thing. So I'm gonna use the translation tool. So I'm gonna start with the translation.
So it says translate by, and this is gonna say so how much do we translate the x coordinates, and how much do we translate the y coordinates? Let's see, if I want to map, if I want to get point W to correspond to this point right over here, which it seems like it should, I would have to go from x equals two, to x equals negative five.
So my x would have to decrease by seven, so let me type that in. Negative seven, and then, let's see, on the y side, and we saw that, by just typing in negative seven, here we moved it to the left by seven. And now, in the y axis, I need to move it down by, let's see, one, two, three, four.
So my y coordinates, I move it down by four. And let's see. What happens? And it looks like I was able to successfully translate it by translating x by negative seven, every point here, every point on this has been shifted to the left by seven, and has been shifted down by four.
And I was able to get onto this triangle. I was able to, through the translation, the image is now in kind of that target triangle that they asked me to map to, to translate to. We got it right.
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