1) 5(2-5х)-7(4х-1) =6х
10 -25x -28x +7=6x
-53 x -6x= -17
-59x = -17|÷(-59)
x= 17/59
2)2(8х-1)-8(2х-3) =13
16x -2 - 16x + 24 = 13
22=13
3)7(2х+3)+х=4х-12
14x+21+x=4x-12
11x= -33
x=-3
4)4 (5х-1) =3х+13
20x-4 = 3x+13
17x=17
x=1
5)2 (4х+3)-5х=3
8x+6-5x=3
3x=-3
x=-1
6)9+2(7х+6)=5х+12
9+14x+12=5x+12
9x=-9
x=-1