Solving LinkedIn Mini Sudoku #184: Isosceles Triangle

Game: LinkedIn Mini Sudoku | Puzzle ID: 184 | Puzzle Name: Isosceles🔺

LinkedIn's 6x6 Sudoku puzzles offer a quick but challenging brain teaser. Today's puzzle, the Isosceles Triangle, requires logical deduction to fill all empty cells. Let's break down the solving process step-by-step.

Understanding the Rules

Before diving into the solution, remember that each row, column, and 2x3 box must contain all digits from 1 to 6 exactly once. With only a few starting clues, we'll use logical elimination to find each missing number.

Starting Position Analysis

Our puzzle begins with these clues:

• Row 1: 5 in position 4
• Row 2: 4 in position 3, 3 in position 5
• Row 3: 5 in position 3, 2 in position 5
• Row 4: 2 in position 2, 1 in position 6
• Row 5: Complete row with 1, 2, 3, 4, 5 (missing only 6)
• Row 6: Completely empty

Step-by-Step Solution Strategy

Step 1: Solve Row 5 Immediately

Row 5 already contains 1, 2, 3, 4, and 5. The only missing digit is 6, which must go in the first position.

Step 2: Analyze Column Constraints

Now that Row 5 is complete, we can use it to eliminate candidates in columns above:

• Column 2 now has 2, 1, and will help restrict placements in upper rows
• Column 3 has 4, 5, and 2 from rows 2, 3, and 5
• Column 4 has 5 and 3 from rows 1 and 5
• Column 5 has 3, 2, 4, and 5 from various rows
• Column 6 has 1 and 5 from rows 4 and 5

Step 3: Focus on 2x3 Boxes

Breaking the puzzle into six 2x3 boxes helps narrow down possibilities:

• Top-left box (rows 1-2, columns 1-3): Contains only 4. Needs 1, 2, 3, 5, 6.
• Top-right box (rows 1-2, columns 4-6): Contains 5, 3. Needs 1, 2, 4, 6.
• Middle-left box (rows 3-4, columns 1-3): Contains 5, 2. Needs 1, 3, 4, 6.
• Middle-right box (rows 3-4, columns 4-6): Contains 2, 1. Needs 3, 4, 5, 6.
• Bottom-left box (rows 5-6, columns 1-3): Contains 6, 1. Needs 2, 3, 4, 5.
• Bottom-right box (rows 5-6, columns 4-6): Contains 3, 4, 5. Needs 1, 2, 6.

Step 4: Use the "Only Place" Technique

This powerful strategy identifies numbers that can fit in only one location within a row, column, or box. For example:

• In row 4, we have 2 and 1. Analyzing what numbers are missing and where they can fit helps place 3, 4, 5, and 6.
• Column 1 analysis: Already has numbers in rows 1-5. Row 6 must contain missing digits from previous placements.

Step 5: Systematic Elimination

Work through each empty cell:

• For each cell, list all possible candidates (1-6)
• Cross out numbers already present in that row, column, and box
• When only one candidate remains, fill it in
• Re-evaluate after each placement, as new information eliminates more candidates

Step 6: Complete Rows and Columns

As you fill cells, incomplete rows and columns become easier to solve. When a row needs only one or two numbers, scanning which digits are missing reveals the solution quickly.

For row 4 with clues 2 and 1, identify the missing numbers and determine their positions by checking column and box constraints.

Step 7: Final Box Completion

Once most cells are filled, the remaining empty cells become obvious—each box will need specific digits to reach 1-6.

Key Solving Techniques Used

• Naked Singles: Cells with only one possible candidate
• Box/Line Reduction: Eliminating candidates based on box and row/column intersections
• Hidden Singles: Numbers that can only fit in one place within a row, column, or box

Why This Puzzle Is Called "Isosceles Triangle"

The starting clues form a triangular pattern, reflecting the puzzle's geometric name.

Practice Tips for Future LinkedIn Mini Sudoku Puzzles

• Start with the row or column that has the most clues
• Use pencil marks to track candidates in each cell
• Always check constraints across rows, columns, and 2x3 boxes simultaneously
• Look for "only place" opportunities—they're the fastest solving method
• After placing each number, immediately check which new cells become solvable

Ready to Verify Your Solution?

Follow these logical steps, and you'll complete the Isosceles Triangle puzzle efficiently. For the final answer and additional 6x6 Sudoku puzzles, check our solution page.