Linear equations: watch it solved step by step

Keep the balance: do the same to both sides until x stands alone, then check. Level: KS3 / GCSE. Type any problem of this kind and the Lab works it out and animates every move, with a plain-words explanation of why.

Worked example: 5x - 4 = 2x + 8

1. The equation. An equation is a balance. Our goal is to get x on its own on one side. The golden rule: whatever we do to one side, we must do to the other so it stays balanced.
2. Move the x terms to one side. We want the x terms together on the left, so remove 2x from the right by subtracting 2x on both sides.
3. Move the plain numbers to the other side. The left side still has -4 added on. Undo it by adding 4 on both sides.
4. Divide to get x on its own. x is being multiplied by 3. Undo that by dividing both sides by 3.
5. The solution. x is on its own: x = 4.
6. Check by substituting back. Put x back into the original equation. If both sides come out equal, the answer is right.
7. Both sides match. Both sides equal 16, so x = 4 is correct.

Answer: x = 4

Practise linear equations with problems the Lab marks for you.