TACHS ABILITY • FIGURE MATRICES

Use transformations (addition/subtraction of elements, rotation, shading)

Learn to spot how shapes change across rows and columns so you can find the missing figure.

Why Do We Study Pattern Puzzles?

People have been studying patterns for thousands of years. Figure matrices (grids of shapes that follow a rule) grew out of the idea that you can measure how well someone reasons without using words or numbers. Scientists wanted a fair way to test thinking skills no matter what language you speak.

1936
Raven's Progressive Matrices
John C. Raven created a test using grids of shapes. Each grid followed a hidden rule, and the test-taker had to pick the missing piece. This test became one of the most popular reasoning tests in the world.
1950s
School Entrance Exams Adopt Matrices
Schools began using figure-matrix questions on entrance exams. These puzzles helped measure a student's ability to think logically without relying on reading or math skills.
1970s
Transformation Rules Are Classified
Researchers grouped the rules in figure matrices into categories: adding or removing shapes, rotating shapes, and changing shading. This made it easier to teach students how to solve them.
Today
TACHS and Modern Ability Tests
The TACHS (Test for Admission into Catholic High Schools) uses figure matrices to measure your visual reasoning. Knowing how transformations work gives you a real advantage on test day.

So here is the big question these puzzles answer: Can you figure out the hidden rule that connects a set of shapes, and then use that rule to predict what comes next? Let's learn exactly how to do that.

Core Principles of Transformations

A transformation is any change that happens to a shape as you move across a row or down a column in a figure matrix. There are three main types you need to know for the TACHS.

1

Addition / Subtraction of Elements

Shapes or parts are added to or removed from the figure as you move across a row or down a column. For example, a circle might gain an extra line in each cell.
2

Rotation

A shape turns by a set amount (like 45°, 90°, or 180°) from one cell to the next. The shape stays the same size and form — it just spins.
3

Shading Changes

The fill of a shape changes in a pattern. It might go from empty → striped → solid, or the shaded area might move around the figure.
4

Combined Transformations

Many TACHS questions use two or more rules at once. A shape might rotate AND gain a new element at the same time. Always check for multiple changes.
✦ KEY TAKEAWAY
Think of a figure matrix like a recipe with steps. Each cell is a step in the recipe. If Step 1 is "put dough on a pan" and Step 2 is "add sauce," then Step 3 must be "add cheese" — because each step adds one new ingredient. In a matrix, each cell adds, removes, rotates, or re-shades something following the same kind of steady rule.

Seeing Transformations in Action

The diagram below shows a 3 × 3 figure matrix. Look at each row from left to right. In Row 1, a new line is added inside the circle each time. In Row 2, the arrow rotates 90° clockwise. In Row 3, the square's shading changes from empty to half-filled to fully filled. The missing piece is in Row 3, Column 3.

Row 1 shows addition (one new line per cell). Row 2 shows rotation (the triangle turns 90° each time). Row 3 shows shading (empty → half-filled → ?). The missing piece must be a fully filled square.

When you look at a figure matrix on the TACHS, always scan across each row first, then down each column. Ask yourself: "What changed between Cell 1 and Cell 2?" Then check if the same change happens between Cell 2 and Cell 3. If it does, you have found the rule!

How Each Transformation Works

Addition and Subtraction of Elements

In an addition pattern, a new piece appears in each cell. It could be a dot, a line, a small shape, or an entire new figure layered on top. Count the number of elements in Cell 1, then in Cell 2. If Cell 2 has one more element, you can predict that Cell 3 will have one more still.

In a subtraction pattern, a piece disappears in each cell. The figure gets simpler as you move across the row. Sometimes one row uses addition while another row uses subtraction — so check every row independently.

Rotation

When a shape rotates, it spins around a center point. The most common rotation amounts on the TACHS are 45°, 90°, and 180°. A 90° turn is like turning a book so the top faces to the right. A 180° turn flips it upside down. Pay attention to whether the turn is clockwise (like the hands on a clock) or counterclockwise (opposite direction).

Shading Changes

Shading transformations change the fill of a shape. Common shading patterns include: empty → half-shaded → fully shaded, or a cycle where the shading moves to a different section of the shape. Sometimes shading alternates: shaded → empty → shaded. Think of it like traffic lights cycling through colors in a set order.

💡 Pro Tip
On the TACHS, many questions combine two transformations at once. A shape might rotate AND change its shading at the same time. If you only notice one change, look again — there may be a second rule hiding in the same row.

A Closer Look at Each Transformation Type

The diagram below breaks down the three main transformation types side by side. Each column shows how one cell leads to the next. Study the arrows between the figures to see exactly what changes.

Three columns show how each transformation type progresses. Addition adds one dot per step. Rotation turns the arrow 90° clockwise per step. Shading increases the fill by half per step.
Quick-reference guide for spotting each transformation type
TransformationWhat to Count or TrackCommon Patterns
AdditionNumber of lines, dots, or shapes in each cell+1 per cell, +2 per cell, or elements appear in new positions
SubtractionNumber of elements that disappear each step−1 per cell, outermost layer removed, smallest shape removed
RotationDirection a shape or line is pointing45° CW, 90° CW, 90° CCW, 180° flip
ShadingFill level or shaded region of each shapeEmpty → striped → solid, shading moves to next quadrant

Worked Example: Solving a Figure Matrix

Imagine a 2 × 2 figure matrix (with the bottom-right cell missing). Cell 1 (top-left) has a pentagon with one shaded section and a small dot inside. Cell 2 (top-right) has the same pentagon rotated 90° clockwise, with the shaded section in a new position and two dots inside. Cell 3 (bottom-left) has a hexagon with one shaded section and one dot inside. What does Cell 4 (bottom-right) look like?

Finding the Missing Figure
1
Step 1 — Identify the row ruleCompare Cell 1 to Cell 2 (top row). The pentagon rotated 90° clockwise, the shaded section moved with the rotation, and the number of dots increased from 1 to 2. So the row rule has two parts: rotate 90° CW and add one dot.
Row rule: rotate 90° CW + add 1 dot
2
Step 2 — Check the column ruleCompare Cell 1 to Cell 3 (left column). The shape changed from a pentagon to a hexagon, but the number of dots stayed the same (1 dot) and the shading stayed in the same relative position. So the column rule is: change the shape (add one side) while keeping everything else the same.
Column rule: add one side to the shape
3
Step 3 — Apply both rules to find Cell 4Starting from Cell 3 (hexagon, 1 dot, original position), apply the row rule: rotate the hexagon 90° clockwise and add 1 dot. Or, starting from Cell 2 (pentagon rotated, 2 dots), apply the column rule: change the pentagon to a hexagon (add one side).
Cell 4 = hexagon, rotated 90° CW, with 2 dots inside and the shaded section in the rotated position.
4
Step 4 — Verify with answer choicesLook at the answer choices. Eliminate any option that shows a pentagon (wrong shape), any option with only 1 dot (wrong count), and any option where the hexagon is not rotated. The correct answer is the one that matches all three changes: hexagon + rotated + 2 dots.
Always double-check by reading both the row AND the column.

Strategies, Strengths, and Common Mistakes

Helpful strategies and common pitfalls for figure-matrix questions
StrategyWhy It HelpsWatch Out For
Scan rows first, then columnsMost matrices set the main rule across the row. Checking rows first gives you the fastest path to the answer.Some matrices have a rule that only shows up in the columns. If the row doesn't show a clear pattern, switch to columns.
Count elements in each cellCounting reveals addition or subtraction patterns instantly.Don't just count total elements — also note their positions. Two dots on the left side is different from two dots on the right.
Look for a 'pointer' on the shapeA small notch, arrow, or asymmetric feature tells you when a shape has been rotated.If a shape is symmetric (like a plain circle), rotation alone won't produce a visible change. The rule may be shading instead.
Use eliminationOn the TACHS, you only have 4 answer choices. Ruling out even one wrong option makes guessing easier.Be careful — some wrong answers are 'close' on purpose. They might match one rule but break another.
✦ KEY TAKEAWAY
Think of solving a figure matrix like solving a Sudoku puzzle. You look at what's already there, figure out the rules, and use those rules to fill in the blank. The more you practice spotting patterns, the faster you'll get — and speed matters on the TACHS!

From Simple Matrices to Complex Reasoning

The transformations you learn for the TACHS are the building blocks of more advanced visual reasoning. As questions get harder, you'll see bigger matrices (3 × 3 instead of 2 × 2) and rules that combine three or more transformations at once.

How matrices increase in complexity
FeatureBasic TACHS MatrixAdvanced Matrix
Grid size2 × 2 or 3 × 33 × 3 or larger
Number of rules1–2 per row2–3 per row, sometimes different rules per column
Transformation typesAdd/subtract, rotate, shadeAdd/subtract, rotate, shade, reflection, overlapping, XOR logic
Distractor answersClearly wrong or match only 1 ruleMatch 2 out of 3 rules — very tricky

Don't worry about the advanced level right now. If you master the three core transformations — addition/subtraction, rotation, and shading — you'll have the foundation for all future visual reasoning tasks.

Practice Problems

PROBLEM 1 — CONCEPTUAL
A row of three figures shows a triangle with 1 star inside, then a triangle with 2 stars inside, then a missing figure. What transformation is being used, and what should the missing figure look like?
PROBLEM 2 — BASIC CALCULATION
In a figure matrix, an arrow points UP in Cell 1 and points to the RIGHT in Cell 2. If the same rotation rule continues, which direction does the arrow point in Cell 3? Is the rotation clockwise or counterclockwise?
PROBLEM 3 — INTERMEDIATE
A 3 × 3 matrix has this pattern in Row 1: a square with a black top-left quarter, then a square with a black top-right quarter, then a square with a black bottom-right quarter. What is the shading rule? If Row 2 starts with a circle that has a black left half, what would the next two circles look like?
PROBLEM 4 — APPLIED
In a 2 × 2 matrix: Cell 1 (top-left) shows a white diamond with 2 horizontal lines inside. Cell 2 (top-right) shows a gray diamond with 3 horizontal lines inside. Cell 3 (bottom-left) shows a white hexagon with 2 horizontal lines inside. What does Cell 4 (bottom-right) look like? Identify every transformation at work.
PROBLEM 5 — CRITICAL THINKING
A 3 × 3 matrix has this pattern: across each row, a shape rotates 90° clockwise and one element is removed. Down each column, the shape's shading cycles through empty → striped → solid. If Cell 7 (Row 3, Column 1) is a solid right-pointing arrow with 4 dots, and Cell 8 (Row 3, Column 2) follows the row rules, describe Cell 8 completely. Then explain how you would verify your answer using the column rule.

Putting It All Together

Figure matrices test your ability to spot transformations — the rules that change shapes from one cell to the next. The three main types are addition or subtraction of elements (counting dots, lines, or shapes), rotation (turning a shape by a fixed angle like 45°, 90°, or 180°), and shading changes (empty → half-filled → solid, or shading that moves around the shape).

To solve a TACHS matrix, scan rows first to find the pattern, then check columns to confirm it. Watch for combined transformations — many questions use two rules at once. Use elimination to rule out answer choices that break any of the rules you found. Practice makes these patterns easier to spot quickly on test day!

Varsity Tutors • TACHS Ability • Use transformations (addition/subtraction of elements, rotation, shading)