Bonsoir,
-5/12 + (-11/36)
= -5/12 - 11/36
= (-5 x 3)/(12 x 3) - 11/36
= -15/36 - 11/36
= -26/36
= (-13 x 2)/(18 x 2)
= -13/18
5/9 - 3/10
= (5 x 10)/(9 x 10) - (3 x 9)/(10 x 9)
= 50/90 - 27/90
= 23/90
7/12 - (-5/18)
= 7/12 + 5/18
= (7 x 3)/(12 x 3) + (5 x 2)/(18 x 2)
= 21/36 + 10/36
= 31/36
-5/12 - 11/6 + 5/4
= -5/12 - (11 x 2)/(6 x 2) + (5 x 3)/(4 x 3)
= -5/12 - 22/12 + 15/12
= -12/12
= -1/1
