7-56×4-12+2 13 в столбик
7-56×4-12+2 13=5.1/2 5/6*4=5/3*2=10/3=3.1/3 7-3.1/3=6.3/3-3.1/3=3.2/3 3.2/3-1/2=3.4/6-3/6=3.1/6 3.1/6+2.1/3=3.1/6+2.2/6=5.3/6=5.1/2
7-56×4-12+2 13=5.1/2 5/6*4=5/3*2=10/3=3.1/3 7-3.1/3=6.3/3-3.1/3=3.2/3 3.2/3-1/2=3.4/6-3/6=3.1/6 3.1/6+2.1/3=3.1/6+2.2/6=5.3/6=5.1/2