TY - JOUR T1 - How massive is the black hole at the centre of our Galaxy? A1 - Křížek, Filip A1 - Křížek, Michal A1 - Šolc, Jakub JA - Obzory matematiky, fyziky a informatiky Y1 - 2007 VL - 36 IS - 1 SP - 43 EP - 51 SN - 1335-4981 N2 - Using the formula for calculation of roots of a quadratic equation, Pythagorean theorem, Kepler's laws and observed data, we show that the mass of the black hole at the centre of our Galaxy is more than 3 million Sun masses. ER -