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What does x = 4 actually mean?
Not sure what to do with the number on your car? This page explains it. It takes about two minutes to read.
x is just a number with a cover on
x is not a mystery. It is just a number — but you do not know what number it is until the game tells you.
When your car shows x = 4, the game is telling you: wherever you see x, use 4 instead.
That is all it means. Swap the letter for the number.
Let's try it
- Swap x for 43 × 4 + 1
- Multiply12 + 1
- Add13
The battery says 13. Your answer is 13. They match. Tap it.
Multiply before you add
Look at 3 × 4 + 1.
You must do the multiplication first. 3 × 4 = 12. Then add 1. Answer: 13.
If you added first — 4 + 1 = 5 — then multiplied — 3 × 5 = 15 — you would get the wrong answer.
The rule
Multiply first. Then add or subtract. This applies to every battery in the game.
Follow these with x = 5
- Swap x for 52 × 5 + 3
- Multiply10 + 3
- Add13
- Swap x for 54 × 5 − 7
- Multiply20 − 7
- Subtract13
- Swap x for 510 − 5
- Subtract5
Watch out for these
Thing 1
Leaving x in your answer
Some people write the answer as "3x" and stop there.
Do not stop. You know x = 4. Put the number in and finish the sum.
Thing 2
Adding before multiplying
In 3x + 1, do not add 1 to x first.
Multiply x by 3 first. Then add 1. Multiply always comes before add.