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Lesson 1 of 5

SHORTCUT

The cover-up trick

Cover the x with your thumb and ask what number belongs there.

The question

Solve x + 7 = 12

The trick

Put your thumb over the x and read the sentence out loud. 'Something plus 7 equals 12' — your brain answers it before any algebra happens.

Worked example

  1. 1Cover the x: ☐ + 7 = 12
  2. 2Ask: what plus 7 makes 12?
  3. 35 plus 7 makes 12, so x = 5

So: x = 5

Remember it like this

Thumb on the x, read it like a story. You already know the answer.

In the exam

This is for checking and for building confidence, but write the proper working in the exam: subtract 7 from both sides. Method marks are awarded for the working, not the answer.

Why it works

It turns an algebra problem back into the arithmetic you already trust. The letter was never the hard part — the unfamiliar look of it was.

Explain this to my childGet the words to teach it, in your language

Try it yourself

0/4 correct
  • 1

    x + 5 = 12. What is x?

  • 2

    x − 3 = 9. What is x?

  • 3

    4x = 20. What is x?

  • 4

    x ÷ 3 = 6. What is x?