MathDB
1/x+4/y+9/z=3, x+y+z<=12, x,y,z >0

Source: JBMO 2008 Shortlist A5

October 14, 2017
JBMOalgebrasystem of equations

Problem Statement

Find all triples (x,y,z)(x, y, z) of real positive numbers, which satisfy the system {1x+4y+9z=3x+y+z12\begin{cases} \frac{1}{x}+\frac{4}{y}+\frac{9}{z}=3 \\ x + y + z \le 12 \end{cases}