-3+7 / 4+7 = -3/4
5/7 + 2 = 19/7
-20/ 12 - 2/3 = -7/3
5/6 - -3/5 = 43/30
-2/7 x 1/-5 = 2/35
G= -26 x 5/14
voilaa bon courage !!