# Desargue$$\prime$$s Theorem

The triangles $$A_1B_1C_1$$ and $$A_2B_2C_2$$ are perspective with respect to a center if the lines $$A_1A_2$$, $$B_1B_2$$, and $$C_1C_2$$ are concurrent. They are perspective with respect to an axis if the points $$K=B_1C_1\cap B_2C_2$$, $$L=A_1C_1\cap A_2C_2$$, $$M=A_1B_1\cap A_2B_2$$ are colinear.

Theorem 3 (Desargue$$\prime$$s theorem)

Two triangles are perspective with respect to a center if and only if they are perspective with respect to a point.

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