В прямоугольном треугольнике ABC{"color":"#202335","fontFamily":"stix","language":"ru"} угол A{"color":"#202335","fontFamily":"stix","language":"ru"} равен 90°,{"color":"#202335","fontFamily":"stix","language":"ru"}AB=20,{"color":"#202335","fontFamily":"stix","language":"ru"} AC=21.{"color":"#202335","fontFamily":"stix","language":"ru"} Найдите BC.{"color":"#202335","fontFamily":"stix","language":"ru"}
