Match each point across the line
A mirror line sits halfway between each point and its reflection. Measure straight across, at a right angle to the line: the two distances are equal.
With a vertical line, each point keeps its height and switches sides. The guide lines join matching corners. Their tick marks show equal distances on either side.
Use the same rule horizontally
For a horizontal mirror line, measure straight up and down. Each point keeps its left-to-right position and moves the same distance to the other side.
The long top arm appears at the bottom of the reflection. Both arms still point right. A half-turn would also make them point left, so it would give a different shape.
Check a new shape
Each figure shows the same starting shape on the left. Compare the corners’ heights and distances from the vertical line to choose its mirror image on the right.
Try it
Which figure shows the reflection across the vertical line?
- Figure A.
- Figure B.
Show the answer
Figure B.
B keeps each corner at the same height and the same distance on the other side of the line. The short end stays at the bottom and points left. A moves it to the top, as a half-turn would.
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