1/26х+7/13=9/13х+7/39

1/26х+7/13=9/13х+7/39; 1/26х-9/13х=7/39-7/13; 1/26х-18/26х=7/39-21/39; -17/26х=-14/39; Х=14/39*26/17; Х=28/51;