Equation Square Solver

Equation Square Solver — Step by Step

Click a sign to change it (+ → − → × → ÷), click an answer box to type it, and click a square to type a given number. Then press Solve. Or play a generated puzzle and send it here with one click.

Equation Square Solver: rules, how to use it, tips

Place 1 to 9 once each so every row and column, worked through with its signs, gives the answer at its end.

The rules

Each number from 1 to 9 is used exactly once.
Rows are worked from left to right and columns from top to bottom.
Classic working does one step at a time: 2 + 3 × 4 = 5 × 4 = 20. BODMAS working does × and ÷ first: 2 + 3 × 4 = 14.
Every division must come out exactly.

Using the solver

Choose left-to-right or BODMAS working, set the twelve signs and six answers, and add any given numbers — or press Sample.
Press Solve and step through each equation: the ways it can be made, and which numbers that leaves.

Tips

Start with ÷. A line with division can only use pairs that divide exactly — often just a handful.
Big answers need ×. An answer like 72 needs a large product; small answers with × usually involve 1 or a subtraction.
Odd and even. With + and −, the answer’s odd or even tells you how many odd numbers the line holds.
Work backwards. In a left-to-right line a op b op c = R, undo the last step: (a op b) must equal R undone by c.

The full guide, with a worked example and common mistakes: How to play Equation Square.

Questions

What’s the difference between the two workings?

Left to right does each step in order. BODMAS does multiplication and division before addition and subtraction, like a calculator.

Can an answer be negative?

Not in the puzzles generated here, but the solver accepts negative answers.

Is there always one answer?

Yes — every puzzle here is checked to have exactly one solution.

How do I solve one from a book?

Open the Equation Square Solver, set the signs and answers and press Solve.