Question

Rezolvati ecuatiile:
c) 5*(3,4+2*x)-12,3=10
d) 2,5*(16,5*x-18,72=52,2
e) 1,5*{5+2.5*[7+5,5*(3250:100-x)]}=75
f) [(2,4 la puterea 2 :2,52)*0,2 la puterea a 2 +1,8 la puterea a 2]:0,2 la puterea a 2=84

Answer 1

c) 5(3,4+2x)-12,3=10
17+10x=10+12,3
10x=22,3-17
10x=5,3
x=5,3/10
x=0,53

d) 2,5(16,5x-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

e) 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

f) [(2,4² :2,52)·0,2² +1,8²]:0,2²=84
[(5,76 :2,52)·0,04 +3,24]:0,04=84
[(576/100):(252/100)·4/100+324/100]:4/100=84
[(576/100)·(100/252)·4/100+324/100]:4/100=84
[(576/252·4/100+324/100]:4/100=84
[(576/63·1/100+324/100]·100/4=84
[(576/6300+324·63/6300]·100/4=84
20988/6300·100/4=84
5247/63-84=
(5247-84·63)/63=-45/63=-15/21=-5/7