Question

Va rog frumos, exercitiul 16 si 17 (dau coroana + 30pct)

Answer 1

Explicație pas cu pas:

16.

1,1(3)=(113-11)/90=102/90=34/30

1,1(6)=(116-11)/90=105/90=35/30

1,8(3)=(183-18)/90=165/90=55/30

x*34/30=35y/30=55z/30=>

34x=35y=55z=k =>

x=k/34

y=k/35

z=k/155

x+y-3z=135=>9k/2618=135=>k/2618=15 =>k=2618*15 =>

x=2618*15/34=77*15=1155

y=2618*15/35=1122

z=2618*15/55=714

17.

12a=6b=3c=k =>

b=2a si c=4a

a²b/c+b²c/a+c²a/b=98 =>

2a³/4a+16a³/a+16a³/2a=98=>

a²/2+16a²+8a²=98*2=>

a²+32a²+16a²=98*2=>

49a²=98*2=>a²=4=>a=2 sau a=-2

=>b=4 sau b=-4

=>c=6 sau c=-6