Basic Geometry
Time: 20 minutes Total Marks: 30
Instructions: Answer all questions. For True/False items you must give a short justification. Use where needed.
Section A — Multiple Choice (1 mark each)
Choose the single correct option.
Q1. Which has two endpoints and a fixed length? (a) line (b) ray (c) line segment (d) point
Q2. An angle measuring is: (a) acute (b) right (c) obtuse (d) reflex
Q3. The complement of a angle is: (a) (b) (c) (d)
Q4. When a transversal crosses two parallel lines, alternate angles are: (a) supplementary (b) equal (c) complementary (d) reflex
Q5. A triangle with all sides of different length is called: (a) equilateral (b) isosceles (c) scalene (d) right
Q6. A quadrilateral with exactly one pair of parallel sides is a: (a) rhombus (b) trapezium (c) kite (d) rectangle
Q7. A chord that passes through the centre of a circle is the: (a) radius (b) arc (c) diameter (d) sector
Q8. The circumference of a circle of radius is: (a) (b) (c) (d)
Q9. A 3D shape with 6 identical square faces is a: (a) cuboid (b) cylinder (c) cube (d) prism
Q10. The order of rotational symmetry of a square is: (a) 1 (b) 2 (c) 3 (d) 4
Section B — Matching (5 marks)
Q11. Match each shape/term to its property. Write pairs like A–iii.
| Column X | Column Y |
|---|---|
| A. Rectangle | i. All sides equal, all angles |
| B. Square | ii. Opposite sides equal, all angles |
| C. Straight angle | iii. Boundary length of a polygon |
| D. Perimeter | iv. Measures exactly |
| E. Radius | v. Half of the diameter |
Section C — True / False with justification (2 marks each: 1 verdict + 1 reason)
Q12. The interior angles of any triangle add up to .
Q13. All rectangles are squares.
Q14. Two angles that are supplementary add up to .
Q15. A cube has 12 edges.
Q16. A parallelogram has exactly two lines of symmetry.
Q17. The exterior angle of a triangle equals the sum of the two opposite interior angles.
Q18. Perpendicular lines meet at a angle.
Q19. The area of a triangle with base and height is .
Q20. A net of a cube is made of 6 squares.
Answer keyMark scheme & solutions
Section A (1 mark each)
Q1. (c) line segment — a segment is bounded by two endpoints; a line/ray are unbounded. (1)
Q2. (c) obtuse — lies between and . (1)
Q3. (b) — complementary angles sum to ; . (1)
Q4. (b) equal — alternate angles between parallel lines are congruent. (1)
Q5. (c) scalene — no two sides equal. (1)
Q6. (b) trapezium — defined by exactly one pair of parallel sides. (1)
Q7. (c) diameter — longest chord, through the centre. (1)
Q8. (b) — standard circumference formula ( is area). (1)
Q9. (c) cube — six congruent square faces. (1)
Q10. (d) 4 — a square maps onto itself at . (1)
Section B
Q11. A–ii, B–i, C–iv, D–iii, E–v. (1 mark each correct pair = 5)
Section C (1 verdict + 1 reason)
Q12. True. Angle sum property of a triangle is exactly . (2)
Q13. False. A square requires all four sides equal; a rectangle only needs opposite sides equal, so not every rectangle is a square (though every square is a rectangle). (2)
Q14. False. Supplementary angles sum to ; those summing to are complementary. (2)
Q15. True. A cube has 6 faces, 8 vertices and 12 edges. (2)
Q16. False. A general parallelogram has no lines of symmetry (it has rotational symmetry of order 2). (2)
Q17. True. Exterior angle theorem: exterior angle = sum of two remote interior angles. (2)
Q18. True. By definition perpendicular lines intersect at . (2)
Q19. False. Correct formula is ; the given expression is twice the area. (2)
Q20. True. A cube has 6 square faces, so its net consists of 6 squares. (2)
[
{"claim":"Complement of 40 degrees is 50","code":"result = (90 - 40 == 50)"},
{"claim":"Triangle angle sum is 180","code":"result = (60 + 60 + 60 == 180)"},
{"claim":"Cube has 12 edges (Euler: V-E+F=2, V=8,F=6)","code":"V,F=8,6; E=V+F-2; result = (E==12)"},
{"claim":"Area of triangle is half base times height, not base times height","code":"b,h=symbols('b h'); result = (Rational(1,2)*b*h != b*h)"}
]