Question

Determine o valor de x + y + z, sabendo - se que X/4=Y/12=Z/20 e 3.x + 2.z = 39

Answer 1

Vamos lá!!!!
3x+2z=39
x/4=y/12=z/20
transforma tudo em Y
x/4=y/12
x=y/3
z=5y/3
3y/3+10y/3=39
13y/3=39
13y=117
y=117/13=9
x=y/3= 9/3 = 3
z=5*9/3= 15
9+3+15=27

Answer 2

Boa noite

x/4 = y/12 = z/20,
3x + 2z = 39

y = 3x 
z = 5x 
x + y + z = x + 3x + 5x = 9x 

x = z/5 
y = 12z/20 = 3z/5 

x + y + z = z/5 + 3z/5 + z = 9z/5 

9x = 9z/5
45x = 9z
z = 5x
3x + 10x = 39
13x = 39

x = 3
y = 3x = 9
z = 5x = 15 

x + y + z = 3 + 9 + 15 = 27