Bonjour
a = 7/5
b = - 3/10
c = - 4
1. R = ab + c
R = 7/5 * (- 3/10) + (- 4)
R = - 21/50 - 4
R = - 21/50 - (4 * 50) / (1 * 50)
R = - 21/50 - 200/50
R = - 271/50
2. S = ab - bc
S = 7/5 * (- 3/10) - (- 3/10) * (- 4)
S = - 21/50 - 12/10
S = - 21/50 - (12 x 5) / (10 x 5)
S = - 21/50 - 60/50
S = - 81/50
3. T = (a + b) (a + c)
T = (7/5 - 3/10) (7/5 - 4)
T = [(7 x 2) / (5 x 2) - 3/10] [7/5 - (4 x 5) / (1 x 5)]
T = (14/10 - 3/10) (7/5 - 20/5)
T = 11/10 * (- 13/5)
T = - 143/50.
