Question

Aflați pe X din egalitatatile: a) 54-{2X+[(X÷2+12)÷5+24]÷3}÷2=13

b)42-{2X+[(X÷3+17)÷5+27]÷4}÷2=14
Dau coroana celui care răspunde corect și 20 de puncte!!!!

Answer 1

54-{2X+[(X/2+12)/5+24]/3}/2=13
54-{2X+[(X/2+12)/5+24]/3}=13*2
54-{2X+[(X/2+12)/5+24]/3}=26
2X+[(X/2+12)/5+24]/3=54-26
2X+[(X/2+12)/5+24]/3=28
2X+[(X/2+12)/5+24]=28*3
2X+[(X/2+12)/5+24]=84
(X/2+12)/5+24=84-2X
(X/2+12)/5=84-2X-24
X/2+12=(84-2X-24)*5     |*2
X+24=(84-2X-24)*10
X+24=84*10-2X*10-24*10
X+24=840-2X*10-240    |-24
X=840-2X*10-216
X=840-216-2X*10
X=624-2X*10
X=624-2*X*10
X=624-X*20
X=X*21-X*20    ||624=21*X
X=624/21
X=29 rest 15
42-{2X+[(X÷3+17)÷5+27]÷4}÷2=14 
{2X+[(X÷3+17)÷5+27]÷4}÷2=42-14=28
2X+[(X÷3+17)÷5+27]÷4=28*2=56
[(X÷3+17)÷5+27]÷4=56-2X
(X÷3+17)÷5+27=(56-2X)*4
(X÷3+17)÷5=(56-2X)*4-27
(X÷3+17)÷5=56*4-2X*4-27=224-2*4*X-27=224-8*X-27
X÷3+17=(224-8*X-27)*5
X÷3+17=224*5-8*X*5-27*5=1120-40*X-135
X÷3=1120-40*X-135-17
X÷3=1120-135-17-40*X
X÷3=968-40*X      |*3
X=(968-40X)*3
X=968*3-40*X*3
X=2904-120X      |121X-120X=X=121X=2904
X=24