The three planes having Cartesian equations $2x + 3y - z = 11,{\text{ }}x + 2y + z = 3$ and $5x - y - z = 10$ meet at a point $P$. Find the coordinates of $P$.

using technology and/or by elimination (eg ref on $GDC$)     (M1)

$x = 1.89{\text{ }}\left( { = \frac{{17}}{9}} \right),{\text{ }}y = 1.67{\text{ }}\left( { = \frac{5}{3}} \right),{\text{ }}z =  - 2.22{\text{ }}\left( { = \frac{{ - 20}}{9}} \right)$     A1A1A1

Note:     Award A1A1A0 for a set of correct answers not given exactly or to three significant figures.

[4 marks]