Question 79
Two parallel chords $AB$ and $CD$ are constructed on the hyperbola $y = 1/x$. The lines $AC$ and $BD$ meet ordinate axis $Oy$ at points $A_1$ and $D_1$ respectively, and meet abscissae axis $Ox$ at points $C_1$ and $B_1$ respectively.
Prove that the areas of the triangles $A_1OC_1$ and $D_1OB_1$ are equal.
Prove that the areas of the triangles $A_1OC_1$ and $D_1OB_1$ are equal.