How to play

  • The variables represents unique integers ranging from 1 to the number of variables;
  • Multiplication is implicit: AB means A times B, or A * B;
  • Based on the clues (equations and inequations), use the grid to create relations between variables and values:
    • Click once on a square to mark that value as false;
    • Click twice to assign the chosen value to the variable;
    • Click three times to clear the square.
  • The color of a clue changes after you assign values to all of its variables:
    • GREEN means that the statement is true;
    • RED means that the statement is false.
  • Click on a clue to mark it as used;
  • The game ends when all values are correctly assigned to the variables.


  • Figuring out which variables can't have the lowest or the highest values is a good starting point, e.g, A > B shows that A ≠ 1;
  • Analyzing the hypothetical equation C + D = 4, we can make the following statements:
  • Another quick tip: A = 2B means that A is even;
  • Don't be afraid of using pen and paper. Some puzzles might require it.

More 9x9 puzzles

  • 2F = E
  • A > F
  • 3H = 4B
  • 2A = 3G
  • 4H = 2D
  • G > C


  • 4A = 3G
  • 4D = 2H
  • C > A
  • H = 4F
  • 3I = B


  • 2A = D + H
  • D > E
  • 2B = C + E
  • 2D = E + H
  • 2D = B + I
  • 2E = A + F


More games

Zebra Puzzles
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Choose nine unique number using one simple rule.

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Logic Grid Puzzles
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Complete the grid by using logic and the given clues of each problem.