Răspuns:
4. a) 34-2(2 660+76:x):893= 28
( -5320-152/x):893= -6
-5320-152/x=-5 358
152(35+1/x)=5358
35+1/x= 32.25
1/x=-2.75 => x=-0.36
B) 51-(2660×76+x):23=28
-(202 160+x)= -23/23
202 160+x= 1
x= -202 159
5. a) (100-x:76)×35+1=876
100-x:76=875:35
-x:76= -75 => x=75×76= 5 700
b) ((100+x):75-1)×35=875
(100+x):75=25
100+x= 1 875
x= 1775
6. a) 5^4:5^2+5(55-x)=5^3
5^2+5(55-x)=5^3
25+ 275-5x= 75
-5x=-225 => x=45
b) 25^14:25^12-5(55+x/5)=25
25^2 - 275- x= 25
-x=25-625+275 => x=325
