,

กำหนดหมายเลขสมการ

$$\begin{eqnarray*} xy+yz & = & 35\quad\cdots(1)\\ yz+xz & = & 32\quad\cdots(2)\\ xz+yx & = & 27\quad\cdots(3) \end{eqnarray*}$$

$(1)+(2)+(3)$ ได้

$$\begin{eqnarray*} 2\left(xy+yz+xz\right) & = & 94\\ xy+yz+xz & = & 47 \quad\cdots(\star) \end{eqnarray*}$$

,

$$\begin{eqnarray*} xz & = & 12\quad\cdots\left(4\right)\\ xy & = & 15\quad\cdots\left(5\right)\\ yz & = & 20\quad\cdots\left(6\right) \end{eqnarray*}$$

,

$$\begin{eqnarray*} \frac{\left(4\right)\times\left(5\right)}{\left(6\right)}:\qquad x^{2} & = & 9\\ \frac{\left(5\right)\times\left(6\right)}{\left(4\right)}:\qquad y^{2} & = & 25\\ \frac{\left(4\right)\times\left(6\right)}{\left(5\right)}:\qquad z^{2} & = & 16 \end{eqnarray*}$$