Question

doar A,B si C !!!!!!!!!!+

Answer 1

a)[(x-1):100+90]:10-10=0
[(x-1):100+90]:10=10
[(x-1):100+90]=10•10
(x-1):100+90=100
(x-1):100=100-90
(x-1):100=10
x-1=10•100
x-1=1000
x=1001

b)[(x+270:3)•5+100]:600=1
[(x+270:3)•5+100]=1•600
(x+270:3)•5+100=600
(x+270:3)•5=600-100
(x+90)•5=500
(x+90)=500:5
x+90=100
x=100-90
x=10
c)9-(25-16):3=[18-3•(9-9) ]:x
9-9:3=[18-3•0]:x
9-3=18:x
6=18:x
x=18:6
x=3