Réponses

2013-03-31T21:33:08+02:00

a) 7 x 8 -9(-9+3)
= 56 +81 -27
= 110

b) 5/6 - 3/4
= 5x2/6x2 - 3x3/4x3
= 10 - 9/12
= 1/12

c) -4/3 x -9/8
= -1/1 x -3/2

= 3/2 ( smeh j'ai pas vu qu'on pouvait simplifier mdr )

d) 3/4 + -9/7
= 3x7/4x7 + -9x4/7x4
= 21 -36/28
= -15/28