Răspuns:
1.
a)(81-2^4 • 5^9 ÷5^8)÷2^2=
(81-2^4 •5) ÷2^2
(81-15×5)÷2^2
(81-80)÷2^2
1÷4= 1/4=2 ^-2
probabil profesoara ta a spus 2 la puterea -2 ;)
b)nu am inteles la ce putere este 2 dar am pus la 8( asta se intelege)
2^16-2^2^4•(9-1)-1•4
2^16-2^4 •8-4
2^16-16 •8-4
2^0•8-4
1×8-=
8-4=4
2.
a)72÷x+2=6
72÷×= 4 | • x
4x=72
x=72×4
x=18;
b)
(3^2)^4=(3^2)^4 x
x=1;
c)2^x+1=2^4
x+1=4
x=3;
d)
5^28-5^24-5(1/5x +55)=25
5^4-x-275=25
625-x-275=25
350-x=25
-×=-325
x=325;
3. nr elevi=36
nr baieti=x
nr fete=5x
x+5x=36
6x=36 | ÷6
x= 6 baieti
fete= 5x
fete=6×5= 30
