Year 9 Factorising and Solving Quadratics Worksheet — Level 3 — Practice Set 2 — 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 2 — Answers
Factorise, then use the null factor law.
1.Solve: 3x2 − 12 = 0
Answer: x = 2 or x = −2
- Factorise: (3x − 6)(x + 2) = 0
- 3x − 6 = 0 gives x = 2
- x + 2 = 0 gives x = −2
2.Solve: 3x2 + 8x − 16 = 0
Answer: x = or x = −4
- Factorise: (3x − 4)(x + 4) = 0
- 3x − 4 = 0 gives x =
- x + 4 = 0 gives x = −4
3.Solve: 2x2 − x − 3 = 0
Answer: x = or x = −1
- Factorise: (2x − 3)(x + 1) = 0
- 2x − 3 = 0 gives x =
- x + 1 = 0 gives x = −1
4.Solve: 3x2 − 11x − 42 = 0
Answer: x = − or x = 6
- Factorise: (3x + 7)(x − 6) = 0
- 3x + 7 = 0 gives x = −
- x − 6 = 0 gives x = 6
5.Solve: 2x2 + 24x + 54 = 0
Answer: x = -3 or x = −9
- Factorise: (2x + 6)(x + 9) = 0
- 2x + 6 = 0 gives x = -3
- x + 9 = 0 gives x = −9
6.Solve: 3x2 + 20x + 12 = 0
Answer: x = − or x = −6
- Factorise: (3x + 2)(x + 6) = 0
- 3x + 2 = 0 gives x = −
- x + 6 = 0 gives x = −6
7.Solve: 2x2 + 19x + 35 = 0
Answer: x = − or x = −7
- Factorise: (2x + 5)(x + 7) = 0
- 2x + 5 = 0 gives x = −
- x + 7 = 0 gives x = −7
8.Solve: 2x2 + 5x − 12 = 0
Answer: x = or x = −4
- Factorise: (2x − 3)(x + 4) = 0
- 2x − 3 = 0 gives x =
- x + 4 = 0 gives x = −4
9.Solve: 2x2 − 10x + 8 = 0
Answer: x = 4 or x = 1
- Factorise: (2x − 8)(x − 1) = 0
- 2x − 8 = 0 gives x = 4
- x − 1 = 0 gives x = 1
10.Solve: 2x2 − 3x − 9 = 0
Answer: x = − or x = 3
- Factorise: (2x + 3)(x − 3) = 0
- 2x + 3 = 0 gives x = −
- x − 3 = 0 gives x = 3
Marking tips
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