Quadratic equations
AQA GCSE Maths revision on Quadratic equations. Aligned to the AQA GCSE Mathematics 8300 specification. This bank has 17 practice questions on this topic.
Sample questions (3 of 17)
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Question 1
Solve x^2 - 5x + 6 = 0. The positive root is...
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Answer: 3
Factorise: numbers that multiply to 6 and add to -5: -2 and -3. (x-2)(x-3) = 0. So x = 2 or x = 3.
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Question 2
Solve x^2 = 16.
- A) x = 4
- B) x = -4
- C) x = +/-4
- D) x = 8
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Answer: x = +/-4
Squaring loses the sign. So both +4 and -4 satisfy: 4^2 = 16 and (-4)^2 = 16. Always write '+/-' for square roots in equations.
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Question 3
The roots of x^2 - 4 = 0 are...
- A) +/-2
- B) +/-4
- C) 2 only
- D) 0 and 4
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Answer: +/-2
x^2 = 4 -> x = +/-2. Or factorise: x^2 - 4 = (x-2)(x+2) = 0 -> x = 2 or x = -2.
Want to test yourself on the remaining cards for this topic?
14 more questions on Quadratic equations — plus mistakes tracking and spaced repetition across the whole Maths spec.