Hint
Use the stated units and precision. Use the full shape description, including exclusions of special cases.
Worked solution
(a)
Use the full shape description, including exclusions of special cases.
The stated shape has 2 reflection axes.
Answer: \(2\)
(b)
Count matching positions during one full revolution.
It matches itself 2 times in a complete turn, including 360°.
Answer: \(2\)
(c)
Use the polygon angle sum, not an assumption that all angles are equal.
For 4 vertices the sum is \(\displaystyle 180(4-2)=360\)°.
Answer: \(360\)
Maths4U indicative marking guidance
Maths4U indicative marking guidance, not an official mark scheme. Credit complete valid alternative methods and consequential reasoning. An unexplained result does not earn a method mark.
(a) · 2 marks
- 1 mark: Use the full shape description, including exclusions of special cases.
- 1 mark: Give the correct requested result, retaining signs, units and any domain restrictions.
Alternative methods: Any complete mathematically valid alternative method with the same restrictions and equivalent exact result is acceptable.
Common error: Keep intermediate values exact until the final step.
(b) · 2 marks
- 1 mark: Count matching positions during one full revolution.
- 1 mark: Give the correct requested result, retaining signs, units and any domain restrictions.
Alternative methods: Any complete mathematically valid alternative method with the same restrictions and equivalent exact result is acceptable.
Common error: Check the answer against the original conditions.
(c) · 2 marks
- 1 mark: Use the polygon angle sum, not an assumption that all angles are equal.
- 1 mark: Give the correct requested result, retaining signs, units and any domain restrictions.
Alternative methods: Any complete mathematically valid alternative method with the same restrictions and equivalent exact result is acceptable.
Common error: Keep intermediate values exact until the final step.
Total: 6 marks.