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## Transformations

Current time:0:00Total duration:1:48

# Performing reflections

CCSS Math: 8.G.A.3, HSG.CO.A.5

## Video transcript

- We're asked to use the
reflect tool to find the image of quadrilateral PQRS, that's this quadrilateral right over here, for a reflection over the line y is equal to x plus two. All right, so let's use the reflect tool. So let me scroll down. So let me click on Reflect, it brings up this tool, and I want to reflect across the line y is equal to x plus two. So let me move this so it is the line y equals x plus two and to think about it, let's see, it's going to have a slope of one, the coefficient on the x term is one, so it's going to have a slope of one, so let me see if I can give this a slope of one. Is this a slope of one? Let me put it a little bit -- yep, it looks like a slope of one as the line moves one to the right. We go from one point of the line to the other, you have
to go one to the right, and one up or two to the right, and two up, however much you move to the right in the x direction, you have to move that same amount in the vertical direction. So now it has a slope of one, and the y intercept is going to be the point x equals zero, y equals two, we see that right over here. When x is equal to zero, y is going to be equal to two, so let me move this. So we see that we now
go through that point. When x is equal to zero, y is equal to two. And now, we just need to reflect PQRS, this quadrilateral, over this line, so let's do that. There you go, we did it. The things, the point, like
point S right over here that was to the top and left of the line, its reflection, the corresponding point in the image is now to
the right and the bottom of the line. The things that were to the right and the bottom of our line, like point P, it's the corresponding
point in the reflection is now on the other side of the line. So there you go, I think we're done, and we got it right.