Question 7

If $\mathbf{u} = x\mathbf{i} + 2\mathbf{j} + 3\mathbf{k}$, $\mathbf{v} = \mathbf{i} + y\mathbf{j} - 3\mathbf{k}$ and $\mathbf{w} = -2\mathbf{i} - 3\mathbf{j}$ represent the sides of a triangle. Find the values of $x$ and $y$.