Two congruent equilateral triangles of side $6\text{cm}$ are joined along a common side to form a rhombus. How many lines of symmetry does the resulting rhombus have?

Step-by-step solution

1. Joining two equilateral triangles along a common side produces a rhombus with all sides equal to $6$ cm.
2. The angles of this rhombus are $60^{c}irc$ and $120^{c}irc$.
3. A rhombus with unequal angles has only the two diagonals as axes of symmetry.
4. Hence there are $2$ lines of symmetry.

Concept tested: Symmetry of a rhombus formed by two triangles

Published 7 October 2026 · How this solution was prepared and checked