Masters trail · ages 16+
Functions practice
Function notation such as f(x) = 2x + 3 is the language of higher maths. Evaluating functions quickly builds confidence with it.
Number Quest's function questions practise substitution and notation with explanations.
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What the questions practise
- Evaluating linear and quadratic functions
- Solving f(x) = a value
- Function notation
Try some example questions
Tap a question to see the answer and how it works.
1. FunctionsIf f(x) = 7x − 8 and f(x) = 41, what is x?841-77
Answer: 7. 7x = 49, so x = 7.
2. FunctionsIf f(x) = 2x − 2, what is f(1)?5-303
Answer: 0. f(1) = 2(1) − 2 = 0.
3. FunctionsIf f(x) = 3x + 5, what is f(5)?16201522
Answer: 20. f(5) = 3(5) + 5 = 20.
Tips for parents and teachers
- Replace x with the number in brackets.
- Use brackets for negatives.
- Check with a quick estimate.
Why Number Quest
Free, with no ads and no in-app purchases. Five trails from age 5 to 16+, five ways to play, a daily goal that builds a streak, buddies to unlock and a friendly weekly leaderboard. Questions are made fresh on the device, so there is always something new.
An Android app on Google Play is coming soon. Until then, play free right here in your browser.