svp aidez mwa urgent

bonjour

Exercice 1

R = abc
R = -5 x - 8 x - 3
R = - 120

S = 2 a - 3 b
S = 2(-5) - 3( -8)
S = - 10 + 24 
S = 14

U = ab + cd
U = 40 + ( - 21)
U = 40 - 21
U = 19

Y = a/b +[ ( a - d)/(b - c)]
Y = - 5/ - 8 + [( - 5 - 7) : ( - 8 +3)]
Y = - 5 /-8 + (-12 /- 5)
Y = 5/8 + 12/5
Y = 25/40 + 96/40
Y = 121/40

dans l'exercice 2, les chiffres sont quasi invisibles