Year 5 · Reflection and translation · Summary

Year 5 Reflection and translation: summary and key words

Part of the Year 5 reflection and translation chapter. Chapter overview · whole chapter on one page

Chapter summary

Skill	Method
Translation	A slide. Every point moves the same distance, in the same direction. Describe it as squares across (right or left), then up or down.
Reflection	A flip over a mirror line. Each point and its image are the same distance from the line, on opposite sides.
Mirror line	The line the shape is flipped over. In these pictures it is dashed and red.
Image	The new shape after a move. Its corners are named with a dash, so the image of A is A'.
Same size and shape	A translation or a reflection keeps the size and shape. The shape has not changed.
Changed	A shape made bigger or stretched has changed, so it is not a translation or a reflection of the first shape.
Drawing a translation	Move every corner the same number of squares across and up or down.
Drawing a reflection	Count from each corner to the line, then the same number of squares on the other side.

I can describe a translation by the squares across and the squares up or down.
I can draw a translation by moving every corner the same way.
I know a reflection flips a shape over a mirror line, and the image is the same distance from the line on the other side.
I can draw a reflection in a vertical or a horizontal mirror line.
I can find the mirror line when I know a point and its image.
I know that a translation or a reflection keeps the size and shape, so the shape has not changed.
I can explain the difference between a translation and a reflection.

Translation: A move that slides a shape. Every point moves the same distance in the same direction.
Reflection: A move that flips a shape over a mirror line.
Mirror line: The line that a shape is flipped over in a reflection.
Image: The new shape made by a translation or a reflection.
Across: Sideways, to the right or to the left.
Vertical: Going up and down.
Horizontal: Going across, from side to side.
Corner: A point where two sides of a shape meet.