bd = 6
Объяснение:
P abc = ab + bc + ac = ab + bc + ad + dc
P abd = ad + bd + ab
P bdc = dc + bd + bc
P abd + P bdc = ad + bd + ab + dc + bd + bc = ac + ab + bc + 2bd =
= P abc + 2bd;
P abd + P bdc = P abc + 2bd
28 + 32 = 48 + 2bd
12 = 2bd
bd = 6
Объяснение:
P abc = ab + bc + ac = ab + bc + ad + dc
P abd = ad + bd + ab
P bdc = dc + bd + bc
P abd + P bdc = ad + bd + ab + dc + bd + bc = ac + ab + bc + 2bd =
= P abc + 2bd;
P abd + P bdc = P abc + 2bd
28 + 32 = 48 + 2bd
12 = 2bd
bd = 6