Question

Va rog mult ajutatima
Aflati x
A) 5*(3,4+2*x)-12,3=10
B) 2,5*(16,5*x-18,72)=52,2
C) 1,5*{5+2,5*[7+5,5(3250:100-x)]}=75
D) [(2,4 la puterea 2:x+2,52)*0,2+1,8 la puterea 2]:0,2 la puterea 2=84
Dau 40 puncte si coroana

Answer 1

a)

5•(3,4+2•x)-12,3=10

5•(3,4+2•x)=10+12,3

5•(3,4+2•x)=22,3

3,4+2x=22,3:5

3,4+2x=4,46

2x=4,46-3,4

2x=1,06

x=1,06:2

x=0,53

b)

2,5•(16,5•x-18,72)=52,2

41,25x-46,8=52,2

41,25x=52,2+46,8

41,25x=99

x=99:41,25

x=2,4

c)

1,5•{5+2,5•[7+5,5•(3250:100-x)]}=75

5+2,5•[7+5,5•(32,5-x)]=75:1,5

5+2,5•[7+5,5•(32,5-x)]=50

2,5•[7+5,5•(32,5-x)]=50-5

2,5•[7+5,5•(32,5-x)]=45

7+5,5•(32,5-x)=45:2,5

7+5,5•(32,5-x)=18

5,5•(32,5-x)=18-7

5,5•(32,5-x)=11

32,5-x=11:5,5

32,5-x=2

x=32,5-2

x=30,5

d)

Scuze,dar la d nu știu.