{ x; y; z} dp { 3; 4; 6} => [tex]\frac{x}{3} =\frac{y}{4} =\frac{z}{6} =k[/tex]=> x=3k; y=4k; z=6k
a)
z - y + x = 10
6k - 4k +3k =10
2k +3k =10
5k=10=> k=2. => x=6; y=8; z=12
b)
x+y-z=4
3k+4k-6k=4
7k-6k=4
k=4=> x=12; y=16; z=24
c)
y+z-x=21
4k+6k-3k=21
10k-3k=21
7k=21
k=3=> x=9; y=12; z=18
