. bonjour esque quelqu’un peu me m'expliquer svp ;)

Bonsoir,

a) - 15/8 x 27/ - 12 x - 7/5
= - 15/8 x - 27/12 x - 7/5
= 405/96 x - 7/5
= - 2835/480
= 15 x - 189 / 15 x 32
= - 189/32

b) - 6/- 8 x - 10/ - 9 x 56/3
= 6/8 x 10/9 x 56/3
= 60/72 x 56/3
= 3360/216
= 24 x 140 / 24 x 9
= 140/9