About this video
Sal translates polygons on a grid. T with subscript (5, 2) means move every point 5 right and 2 up, so (3, 3) goes to (8, 5). In the second example he moves points 8 to the left and 2 down.
You'll be able to
- read translation notation like T(5, 2).
- translate a point by adding to its x and y coordinates.
- handle negative translations that move left or down.
Key words
- translation
- Sliding a shape without turning or resizing it.
- image
- The shape or point after the transformation.
- horizontal
- Left-right direction, which changes the x-coordinate.
- vertical
- Up-down direction, which changes the y-coordinate.
Transcript
What is the image of the polygon below after the translation is capital T with the subscript 5 comma 2? So that means let's translate 5 in the horizontal direction and 2 in the vertical direction. So let's do that. So I'm going to focus on this point right over here.
So that point is at the point 3 comma 3. If I want to translate five in the horizontal direction, the x value is going to get to 8. So the x value is going to 1, 2, 3, 4, 5. And then we want to increase the y value by 2. 1, 2. Let's check our answer. Let's do a couple more of these.
That was lot of fun. So here we need to shift it by negative 8 in the horizontal direction. So this one right over here, it's x value is 0, so we need to go essentially negative 8, negative 1, negative 2, or we move to the left 1, 2, 3, 4, 5, 6, 7, 8. And then we have to move it down by 2.
So we have to move down 1, move it down 2. And we're done.
Video © Khan Academy, used under CC BY-NC-SA. Watch on Khan Academy. Puzzicle is not affiliated with Khan Academy.