PuzzleM8 Learning games for families

One-step equations

Solve x + 8 = 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 + 8 = 9The question.

  2. Step 1: Subtract 8 on both sides −8

    On the left, the x part has + 8 with it. Take 8 away from both sides to get rid of it.

    x = 1

    On the left, the 8 cancels out. x is on its own. x = 1.

    + 8 is undone by − 8.

Answer: x = 1

Check it

Put x = 1 back into the question. If both sides come to the same number, the answer is right.

Left side: x + 8 → 1 + 8 = 9

Right side: 9 → 9

✓ Both sides are 9, so x = 1 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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