Explicație pas cu pas:
1) 0
2) 10
3) 5
4) 5
5) 90
6) 18
Sub 2
2) 2x=3y=4z=k=> [tex]x=\frac{k}{2}[/tex]
[tex]y=\frac{k}{3}[/tex]
[tex]z=\frac{k}{4}[/tex]
k/2* k/3+k/3*k/4+k/2*k/4=54
=> [tex]\frac{k^{2} }{6} +\frac{k^{2} }{12} +\frac{k^{2} }{8} =>\frac{9k^{2} }{24}=54 =>k=\sqrt{\frac{54*24}{9} }=\sqrt{144} =12[/tex]
3) a=b+2
(a-3)*2=b+3
(b+2-)*2=b+3
(b-1)*2=b+3
2b-2=b+3
2b=b+5=>
b=5
a=5+2=7
a+b=12
