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, 2016

Geometry Difficulty 2.6 Junior Find the answer Canada

Triangle $T$ is reflected once.Hide/Reveal Description of Triangles Triangle A> Starting at the vertex of the 90 degree angle, the shorter side goes up and the longer side goes left. Triangle B> Starting at the vertex of the 90 degree angle, the shorter side goes up and the longer side goes left. Triangle C> Starting at the vertex of the 90 degree angle, the shorter side goes up and the longer side goes right. Triangle D> Starting at the vertex of the 90 degree angle, the shorter side goes down and the longer side goes left. Triangle E> Starting at the vertex of the 90 degree angle, the shorter side goes down and the longer side goes left. Which of the following triangles cannot be this reflection of triangle $T$ ?

Pick one

Solution

Each of the following four diagrams shows the image of triangle $T$ after its reflection in the dotted line. [[IMAGE0]] Thus, each of the triangles labelled $A, B, D,$ and $E$ is a single reflection of triangle $T$ in some line. The triangle labelled $C$ is the only triangle that cannot be a reflection of triangle $T$ .

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.