1)
1,2*(3b+5) = 2*(2,4b-3,6),
3,6b + 6 = 4,8b - 7,2,
3,6b - 4,8b = -7,2-6,
-1,2b = -13,2,
b = 11,
2)
(5,8x-40,1)/0,8 = (3,2x-23,9)/(-2,4),
-3*(5,8x - 40,1) = 3,2x - 23,9,
-17,4x + 120,3 = 3,2x - 23,9,
-17,4x - 3,2x = -23,9 - 120,3,
-20,6x = -144,2,
x = 7