Question

Va rog ecercitiile 30 si 31!!

Answer 1

30) (a+b+c)/3=70 => a+b+c=210
2a=3b=> a=3b/2
10b=4c => c=10b/4=5b/2
3b/2+b+5b/2=210 /x2
3b+2b+5b=420
10b=420 => b=42
a=3b/2= 63
c=5b/2=105
31)a=4k
b=5k
c=3k
a^2+c^2= (4k)^2+(3k)^2
=16k^2+9k^2=25k2=pătrat perfect
a+b+c=36
4k+5k+3k=36
12k=36 => k=3
a=12
b=15
c=9