Exercitiul 84.
b=5+(8:2) => b= 5+4 => b=9
a=3xb => a= 3 x 9 => a=27
c= 2 x b + a => c= 2 x 9 +27 => c= 18+27=>c=45
a+b+c+d=100 => 27+9+45+d=100 =>81+d=100=>d=19
c-d=45-19=>c-d=26
Exercitiul 85
a=(9+8:2-9:3):2=(9+4+3):2=16:2=8
b=7-15 : (8-6:2)=7-15:5=7-3=4
c=(8+16):3+3 x (18-4x3)=24:3+3 x (18-12)=8+3 x 6=8+18= 26
5 x a +3 x b - c =5 x 8 + 3 x 4 - 26= 40+12-26= 26
8 x a +6 x b - 2 x c= 8 x 8+6 x 4 - 2 x 26= 61+24+52=137
