∑ DANEMATHICS
FREE CAPS MATHS RESOURCES
Grade 10 · Exponents, Equations and Inequalities
Linear Inequalities & Interval Notation (Grade 10)
MEMORANDUM
Name:
Class:
Date:
Mark
/ 15
Answer all questions. Show all your working — marks are awarded for method as well as the final answer. Teacher copy: accept any correct equivalent method.
- 1Solve: 2x + 3 < 11(2)2x < 8 → x < 4, i.e. (−∞ ; 4)✓✓ (2)
- 2Solve: 5x − 4 ≥ 16(2)5x ≥ 20 → x ≥ 4, i.e. [4 ; ∞)✓✓ (2)
- 3Solve: −2x > 10(2)x < −5 (sign flips), i.e. (−∞ ; −5)✓✓ (2)
- 4Solve: −3x + 1 ≤ 7(2)−3x ≤ 6 → x ≥ −2, i.e. [−2 ; ∞)✓✓ (2)
- 5Write x > 5 in interval notation.(1)(5 ; ∞)✓ (1)
- 6Write −2 ≤ x ≤ 7 in interval notation.(1)[−2 ; 7]✓ (1)
- 7Write (−∞ ; 3] as an inequality.(1)x ≤ 3✓ (1)
- 8Solve: −4 < 2x − 2 ≤ 6(3)−1 < x ≤ 4 → (−1 ; 4]✓✓✓ (3)
- 9On a number line, what does an OPEN circle mean?(1)The value is not included (< or >).✓ (1)
TOTAL: 15 marks