a) x + 30%x = -1,31
(1 + 30%)x = -1,31
13/10x = -1,31
x = -1,31 : 13/10
x = -131/130
b) (x - 1/2) : 1/33 + 5/7 = 68/7
(x - 1/2) : 1/33 = 68/7 - 5/7
(x - 1/2) : 1/33 = 9
(x - 1/2) = 9 x 1/33
x - 1/2 = 3/11
x = 3/11 + 1/2
x = 17/22
c) (4,5 - 2x) . ( -11) = 11/14
(4,5 - 2x) = 11/14 : (-11)
(4,5 - 2x) = -1/14
2x = 4,5 + 1/14
2x = 32/7
x = 16/7
a,x + 30%x = -1,31
x.130%= -1,31
x = -131/130
b, (x-1/2) : 1/33 + 5/7 = 68/7
(x-1/2) . 33 = 68/7 -5/7
(x-1/2).33 = 9
x-1/2 = 9:33
x-1/2 = 3/11
x = 3/11 + 1/2
x =17/22
c,(4,5 - 2x).(-11) = 11/14
4,5 - 2x = 11/14 : (-11)
4,5 - 2x = -1/14
2x = 4,5 -(-1/14)
2x = 32/7