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

  • A + E ≤ 9
  • B + E ≤ 16
  • C + G = I
  • D + F ≤ 10
  • F + G = D
  • B + F = G
  • E > H
  • E + H = I

Solve

  • F + G = E
  • E + F = B
  • A + H = C
  • A + G ≤ 6
  • C + G = I
  • A + C ≤ 8

Solve

  • A + I = 5
  • F + H = 7
  • E + F = 6
  • G + I = 6
  • B + I = 9
  • A + D + F = 13

Solve

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