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.

Tips

  • 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

  • E ≤ 1
  • H = C + E
  • H + 8 = A + 2B
  • AE + A = I
  • G = D + 1

Solve

  • CG = C
  • 6C = CE
  • B + 3 ≠ 2A
  • 3I ≥ B
  • F ≠ A + D
  • F = C + H
  • 3I ≤ 9
  • C + E ≥ A
  • A + F + H + 1 = C + DI
  • E ≠ H + I
  • H > B

Solve

  • E > C + F
  • C > G
  • II < 5
  • BI + F + I = A + B + EG
  • A + D + F = G + 12

Solve

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