How to solve mirror image questions
Reflections: name the axis first
Every reflection happens across a line — vertical, horizontal, or diagonal. Name that line before anything else, and each mirror question becomes a mechanical check.
Updated
Mirror items ask several different questions: reflect a figure across a named line, spot the one option that is NOT a mirror image, find the reflection hidden among rotations, apply two mirrors in a row, or name which line was used. One idea unlocks all of them: a reflection has an axis — the line the figure flips across — and each axis moves squares in its own predictable way.
The four axes
A vertical line swaps left and right and keeps every height. A horizontal line swaps top and bottom and keeps every column. A diagonal line trades the two directions: width and height swap, so check the bounding box first — after a diagonal mirror, a wide figure must be tall. Say which axis the question names before you look at a single option; on axis questions the reflection in the WRONG line is usually among the choices.
Handedness: one flip reverses it, two flips restore it
A single reflection always reverses a figure's handedness — the direction its outline turns as you trace it. A rotation never does. But two reflections in two different lines compose into a pure ROTATION, so on a double-reflection item the correct answer is SAME-handed as the original. 'Reject anything same-handed' is a rule for single-mirror questions only — read the stem before you apply it.
The strategy
- Name the axis the stem asks about — or the two axes, in order, for a double reflection.
- Predict the bounding box: straight axes keep width and height, diagonals swap them.
- Track one distinctive square: a vertical mirror keeps its height, a horizontal mirror keeps its column, a diagonal swaps its two coordinates.
- 'Which is NOT a mirror image?': four options are the same reflection at four different turns — the odd one is the original merely rotated, so judge handedness, not position.
- 'Which line was used?': pick one easy square and see where it went — the mirror line runs at right angles to that journey, halfway along, and every square must agree.
Common traps
- Doing the everyday left-right flip when the stem names another axis.
- A rotation posing as a reflection: it keeps handedness, so tracing the outline exposes it — except on double-reflection items, where same-handed is exactly right.
- Stopping halfway through a double reflection: the figure after only the first mirror is one of the options, and so is the figure after only the second.
Speed · ~30s/item: Axis first, bounding box second, one tracked square third. Single mirrors fall in 15–35 seconds; give double reflections and axis hunts a little longer.
Worked example
Made by the same generator and answer checker as the practice questions, at middling difficulty, but never served in a test. Commit to an option before you reveal — the pick is yours alone and is never recorded.
Which option shows the figure mirrored in the diagonal line running from bottom-left to top-right (↗)?
Reveal the answer
The answer is C.
Show why — the worked reasoning
Try it yourself: 4 practice questions
Pick an answer, then reveal it. Nothing is recorded, there is no clock, and none of these questions is ever used in a test.
Which option shows the figure as seen in a mirror?
Reveal the answer
The answer is E.
Show why — the worked reasoning
Which option shows the figure as seen in a mirror?
Reveal the answer
The answer is C.
Show why — the worked reasoning
Which option shows the figure flipped top-to-bottom, as if mirrored in a horizontal line?
Reveal the answer
The answer is C.
Show why — the worked reasoning
Which option shows the figure as seen in a mirror?
Reveal the answer
The answer is C.
Show why — the worked reasoning
Try questions like this
The free test has 20 questions across abstract, numerical, verbal and spatial reasoning. It takes 12 minutes, needs no sign-up, and explains every answer.
A free account opens every lesson, practice drills and a study plan built from your results.
Questions people ask
Will mirror images questions be on the free test?
Maybe. The free test gives spatial reasoning 4 of its 20 questions, spread across 9 different question types, so any one test may or may not include this kind.