5,37+7,7=8,75+10,3x
5*(4-x)-12=7*(2x-5)

5,37 + 7,7 = 8,75 + 10,3x

13,07 = 8,75 + 10,3x

-10,3x = 8,75 - 13,07

-10,3x = -4,32

x = 216/515

5(4 - x) - 12 = 7(2x - 5)

20 - 5x - 12 = 14x - 35

8 - 5x = 14x - 35

-5x - 14x = -35 - 8

-19x = -43

x = 43/19

x = 2 5/19