3/8 - x = 1/4 -3/20 решите уравнение
3/8-х=1/4-3/20 1/4-3/20=(5-3)/20=2/20=1/10 3/8-х=1/10 -х=1/10-3/8 1/10-3/8=(4-15)/40= -11/40 -х= -11/40 х=11/40