Mrs Lim shows her class four shapes cut from cardboard and asks: "Which of these shapes has at least one line of symmetry?" Which shape should the class choose?
Show Worked Solution
Worked Solution
Step 1: Check the equilateral triangle. All 3 sides are equal and all 3 angles are 60°. A fold through any vertex and the midpoint of the opposite side produces two matching halves. An equilateral triangle has 3 lines of symmetry.
Step 2: Check the scalene triangle. All 3 sides are different lengths. No fold produces two matching halves. 0 lines of symmetry.
Step 3: Check the parallelogram (no right angles). It has rotational but not reflective symmetry. 0 lines of symmetry.
Step 4: Check the irregular trapezium. The two non-parallel sides are of different lengths, so no fold matches both halves. 0 lines of symmetry.
Answer: An equilateral triangle.
Correct answer: An equilateral triangle
Want more questions like this? Superholic Lab has 10,000+ MOE-aligned questions with full worked solutions.
Start Free Trial — 7 Days Free