Find the ordered triple, (p,q,r)
\(\begin{align*} p-2q&=0\\ q-2r&=0\\ p+r&=5. \end{align*}\)
Add equations: (p - 2q) + (q - 2r) + (p + r) = 0 + 0 + 5 ==> 2p - q - r = 5
Divide first equation by 2: p/2 - q = 0
Subtract equations: 5p/2 - r = 0 == > r = 5p/2
Substitute into third equation: p + 5p/2 = 5 ==> 7p/2 = 5 ==> p = 10/7
First equation: p - 2q = 0 ==> q = p/2 = 5/7
Second equation: q - 2r = 0 ==> r = q/2 = 5/14
Solution: (10/7, 5/7, 5/14)