Sagot :
Bonjour,
a)
x = 4/3 +5/4
x= 16/12 + 15/12 = 31/12
b)
x= 5/7 -7/3
x= 15/21 - 49/21 = -34/21
c)
x= 3/12 +5/8
x = 6/24 +15/24
x= 21/24 = 7/8
d)
1/3 +2/9 = x
x =3/9 +2/9 = 5/9
e)
5/18 -11/45 = x
x= 25/90 - 22/90
x = 3/90 = 1/30
f)
x= -11/15 +12/25
x= -55/75 + 36/75
x= -19/75