PuzzleM8 Learning games for families

One-step equations

Solve x − 1 = 9

The aim is to get x on its own. Whatever we do to one side, we do to the other, so the equation stays balanced. This one takes 1 step.

  1. x − 1 = 9The question.

  2. Step 1: Add 1 on both sides +1

    On the left, the x part has − 1 with it. Add 1 to both sides to get rid of it.

    x = 10

    On the left, the 1 cancels out. x is on its own. x = 10.

    − 1 is undone by + 1.

Answer: x = 10

Check it

Put x = 10 back into the question. If both sides come to the same number, the answer is right.

Left side: x − 1 → 10 − 1 = 9

Right side: 9 → 9

✓ Both sides are 9, so x = 10 is right.

Now try it yourself

Solve this one in Algebra Balance. You choose each step, and it explains what happened, with hints if you get stuck.

Practise this in Algebra Balance

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