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: 2x2 + 14x + 20 = 0
Answer: x = -2 or x = −5
- Factorise: (2x + 4)(x + 5) = 0
- 2x + 4 = 0 gives x = -2
- x + 5 = 0 gives x = −5
2.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
3.Solve: 2x2 + 8x − 42 = 0
Answer: x = 3 or x = −7
- Factorise: (2x − 6)(x + 7) = 0
- 2x − 6 = 0 gives x = 3
- x + 7 = 0 gives x = −7
4.Solve: 3x2 − 21x + 18 = 0
Answer: x = 1 or x = 6
- Factorise: (3x − 3)(x − 6) = 0
- 3x − 3 = 0 gives x = 1
- x − 6 = 0 gives x = 6
5.Solve: 3x2 − 13x + 4 = 0
Answer: x = or x = 4
- Factorise: (3x − 1)(x − 4) = 0
- 3x − 1 = 0 gives x =
- x − 4 = 0 gives x = 4
6.Solve: 2x2 + 8x + 6 = 0
Answer: x = -3 or x = −1
- Factorise: (2x + 6)(x + 1) = 0
- 2x + 6 = 0 gives x = -3
- x + 1 = 0 gives x = −1
7.Solve: 2x2 − 7x − 30 = 0
Answer: x = − or x = 6
- Factorise: (2x + 5)(x − 6) = 0
- 2x + 5 = 0 gives x = −
- x − 6 = 0 gives x = 6
8.Solve: 3x2 − 13x − 10 = 0
Answer: x = − or x = 5
- Factorise: (3x + 2)(x − 5) = 0
- 3x + 2 = 0 gives x = −
- x − 5 = 0 gives x = 5
9.Solve: 2x2 − 5x − 18 = 0
Answer: x = or x = −2
- Factorise: (2x − 9)(x + 2) = 0
- 2x − 9 = 0 gives x =
- x + 2 = 0 gives x = −2
10.Solve: 3x2 + 7x + 4 = 0
Answer: x = − or x = −1
- Factorise: (3x + 4)(x + 1) = 0
- 3x + 4 = 0 gives x = −
- x + 1 = 0 gives x = −1
Marking tips
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