Year 11 Factorising and Solving Quadratics Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 11 quadratics worksheet.
Success TutoringWorksheetsAnswer sheetYear 11 · Mathematics · QuadraticsYear 11 Factorising and Solving Quadratics Worksheet — Level 3 — Practice Set 4 — Answers
Factorise, then use the null factor law.
1.Solve: 3x2 + 23x + 40 = 0
Answer: x = − or x = −5
- Factorise: (3x + 8)(x + 5) = 0
- 3x + 8 = 0 gives x = −
- x + 5 = 0 gives x = −5
2.Solve: 2x2 + 16x − 18 = 0
Answer: x = 1 or x = −9
- Factorise: (2x − 2)(x + 9) = 0
- 2x − 2 = 0 gives x = 1
- x + 9 = 0 gives x = −9
3.Solve: 2x2 − 2x − 12 = 0
Answer: x = -2 or x = 3
- Factorise: (2x + 4)(x − 3) = 0
- 2x + 4 = 0 gives x = -2
- x − 3 = 0 gives x = 3
4.Solve: 2x2 + 11x + 12 = 0
Answer: x = − or x = −4
- Factorise: (2x + 3)(x + 4) = 0
- 2x + 3 = 0 gives x = −
- x + 4 = 0 gives x = −4
5.Solve: 2x2 − x − 45 = 0
Answer: x = − or x = 5
- Factorise: (2x + 9)(x − 5) = 0
- 2x + 9 = 0 gives x = −
- x − 5 = 0 gives x = 5
6.Solve: 3x2 − 30x + 48 = 0
Answer: x = 2 or x = 8
- Factorise: (3x − 6)(x − 8) = 0
- 3x − 6 = 0 gives x = 2
- x − 8 = 0 gives x = 8
7.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
8.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
9.Solve: 3x2 − 21x + 30 = 0
Answer: x = 2 or x = 5
- Factorise: (3x − 6)(x − 5) = 0
- 3x − 6 = 0 gives x = 2
- x − 5 = 0 gives x = 5
10.Solve: 3x2 − 21x − 24 = 0
Answer: x = -1 or x = 8
- Factorise: (3x + 3)(x − 8) = 0
- 3x + 3 = 0 gives x = -1
- x − 8 = 0 gives x = 8
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