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![FullSimplify[Solve[{(Y - By)/(Oy - By) == (X - Bx)/(Ox - Bx) == (Z - Bz)/-Bz, (Y - Sy)/(X - Sx) == -Ox/Oy}, {X, Y, Z}]]](../HTMLFiles/index_187.gif){kind=small}
![FullSimplify[Solve[{(Y - By)/(Oy - By) == (X + Bx)/(Ox + Bx) == (Z - Bz)/-Bz, (Y - Sy)/(X - Sx) == -Ox/Oy}, {X, Y, Z}]]](../HTMLFiles/index_188.gif){kind=small}