Répondre :
a=4/5+8/15-3,6/1,5
=4x3/5x3+8/15-3.6x10/1.5x10
= 12/15+8/15-36/15
= 20/15-36/15
= -16/15
b=10/9-7/9x5/3
= 10/9-35/27
= 10x3/9x3-35/27
= 30/27-35/27
= -5/27
a=4/5+8/15-3,6/1,5=
b=10/9-7/9x5/3=
a=4/5+8/15-3,6/1,5
=4x3/5x3+8/15-3.6x10/1.5x10
= 12/15+8/15-36/15
= 20/15-36/15
= -16/15
b=10/9-7/9x5/3
= 10/9-35/27
= 10x3/9x3-35/27
= 30/27-35/27
= -5/27