Year 9 Factorising and Solving Quadratics Worksheet — Level 3 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 9 quadratics worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · QuadraticsYear 9 Factorising and Solving Quadratics Worksheet — Level 3 — Practice Set 3 — Answers
Factorise, then use the null factor law.
1.Solve: 2x2 − 2x − 12 = 0
Answer: x = 3 or x = −2
- Factorise: (2x − 6)(x + 2) = 0
- 2x − 6 = 0 gives x = 3
- x + 2 = 0 gives x = −2
2.Solve: 2x2 − 8x − 24 = 0
Answer: x = -2 or x = 6
- Factorise: (2x + 4)(x − 6) = 0
- 2x + 4 = 0 gives x = -2
- x − 6 = 0 gives x = 6
3.Solve: 2x2 + x − 6 = 0
Answer: x = or x = −2
- Factorise: (2x − 3)(x + 2) = 0
- 2x − 3 = 0 gives x =
- x + 2 = 0 gives x = −2
4.Solve: 3x2 − 10x − 48 = 0
Answer: x = − or x = 6
- Factorise: (3x + 8)(x − 6) = 0
- 3x + 8 = 0 gives x = −
- x − 6 = 0 gives x = 6
5.Solve: 2x2 + 2x − 12 = 0
Answer: x = -3 or x = 2
- Factorise: (2x + 6)(x − 2) = 0
- 2x + 6 = 0 gives x = -3
- x − 2 = 0 gives x = 2
6.Solve: 3x2 − 26x + 35 = 0
Answer: x = or x = 7
- Factorise: (3x − 5)(x − 7) = 0
- 3x − 5 = 0 gives x =
- x − 7 = 0 gives x = 7
7.Solve: 2x2 + 21x + 27 = 0
Answer: x = − or x = −9
- Factorise: (2x + 3)(x + 9) = 0
- 2x + 3 = 0 gives x = −
- x + 9 = 0 gives x = −9
8.Solve: 3x2 − 12x + 9 = 0
Answer: x = 1 or x = 3
- Factorise: (3x − 3)(x − 3) = 0
- 3x − 3 = 0 gives x = 1
- x − 3 = 0 gives x = 3
9.Solve: 2x2 − 7x − 4 = 0
Answer: x = − or x = 4
- Factorise: (2x + 1)(x − 4) = 0
- 2x + 1 = 0 gives x = −
- x − 4 = 0 gives x = 4
10.Solve: 2x2 + 11x + 9 = 0
Answer: x = − or x = −1
- Factorise: (2x + 9)(x + 1) = 0
- 2x + 9 = 0 gives x = −
- x + 1 = 0 gives x = −1
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
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