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CEMC Gauss (Grade 7), 2016

Geometry Difficulty 2.6 Junior Find the answer Canada

Triangle $T$ is reflected once.

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.

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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