Va rog frumos, exercitiul 16 si 17 (dau coroana + 30pct)
![Va Rog Frumos Exercitiul 16 Si 17 Dau Coroana 30pct class=](https://ro-static.z-dn.net/files/dc5/b9fc144524f6e5fba9b7c25354adb4ae.jpg)
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