Math practice · reimagined
Linear functions
Turn Linear functions into a fight you actually want to win. Every problem is an attack — solve it faster than your opponent and you land the hit.
Ages 4–99+ · no download · plays in your browser · 23 languages
How it works
Linear functions
Pick a fighter, choose Linear functions, and trust your numbers. The faster and cleaner you solve, the harder you hit — from gentle early grades all the way to Olympic-level challenges.
Slope is how steep a line is, and it is measured as rise over run: how far the line climbs for every step it takes sideways.
Given two points, subtract the y-values to get the rise and the x-values to get the run, then divide. From (1, 2) to (4, 11): the rise is 11 − 2 = 9, the run is 4 − 1 = 3, so the slope is 3. The line goes up three for every one across.
Order matters only in that you must be consistent — start at the same point for both subtractions, or you will get the sign backwards.
A positive slope climbs to the right, a negative one falls, and a slope of zero is flat. The number is a rate: on a distance-time graph it is speed, on a cost graph it is price per item.
Find the rise, find the run, divide, and type the slope.
— Quick answers —
Linear functions: the short FAQ
- Is Linear functions free to play?
- Yes. Linear functions is free to play right in your browser — the whole curriculum, no download, no signup. Paid plans later unlock the full fighter roster, every stage and saved progress.
- Who is Linear functions for?
- Anyone from 4 to 99+. The early grades stay gentle for beginners, while the higher tiers will make even the confident sweat.
- Do I need to download anything to play Linear functions?
- Nope. Linear functions runs in any browser, on a laptop, tablet or phone.
- Can Linear functions be used in the classroom?
- Absolutely. Teachers run Linear functions with a whole class and track who's improving — see the schools plan for per-student pricing and a teacher dashboard.