Year 12 Factorising and Solving Quadratics Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 12 quadratics worksheet.
Year 12 · Mathematics · Quadratics
Year 12 Factorising and Solving Quadratics Worksheet — Level 3 — Answers
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Factorise, then use the null factor law.
1.Solve: 2x2 + 14x + 12 = 0
Answer: x = -1 or x = −6
- Factorise: (2x + 2)(x + 6) = 0
- 2x + 2 = 0 gives x = -1
- x + 6 = 0 gives x = −6
2.Solve: 3x2 + 3x − 6 = 0
Answer: x = -2 or x = 1
- Factorise: (3x + 6)(x − 1) = 0
- 3x + 6 = 0 gives x = -2
- x − 1 = 0 gives x = 1
3.Solve: 2x2 − 9x − 18 = 0
Answer: x = − or x = 6
- Factorise: (2x + 3)(x − 6) = 0
- 2x + 3 = 0 gives x = −
- x − 6 = 0 gives x = 6
4.Solve: 2x2 − 11x + 5 = 0
Answer: x = or x = 5
- Factorise: (2x − 1)(x − 5) = 0
- 2x − 1 = 0 gives x =
- x − 5 = 0 gives x = 5
5.Solve: 3x2 − 17x + 10 = 0
Answer: x = or x = 5
- Factorise: (3x − 2)(x − 5) = 0
- 3x − 2 = 0 gives x =
- x − 5 = 0 gives x = 5
6.Solve: 3x2 − 11x − 20 = 0
Answer: x = − or x = 5
- Factorise: (3x + 4)(x − 5) = 0
- 3x + 4 = 0 gives x = −
- x − 5 = 0 gives x = 5
7.Solve: 3x2 − 13x + 12 = 0
Answer: x = or x = 3
- Factorise: (3x − 4)(x − 3) = 0
- 3x − 4 = 0 gives x =
- x − 3 = 0 gives x = 3
8.Solve: 2x2 + 11x − 63 = 0
Answer: x = or x = −9
- Factorise: (2x − 7)(x + 9) = 0
- 2x − 7 = 0 gives x =
- x + 9 = 0 gives x = −9
9.Solve: 2x2 + 16x + 14 = 0
Answer: x = -1 or x = −7
- Factorise: (2x + 2)(x + 7) = 0
- 2x + 2 = 0 gives x = -1
- x + 7 = 0 gives x = −7
10.Solve: 2x2 − 12x + 18 = 0
Answer: x = 3 or x = 3
- Factorise: (2x − 6)(x − 3) = 0
- 2x − 6 = 0 gives x = 3
- x − 3 = 0 gives x = 3
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