18. Choose a point $(\mathrm{x}, \mathrm{y})$ on the coordinate plane such that its distances to the $x$-axis, $y$-axis, and the line $x+y=2$ are all equal. Then $\mathbf{x}$ is
(A) $\sqrt{2}-1$; (B) $\frac{1}{2}$;
(C) $2-\sqrt{2}$;
(D) 1 ;
(E) not uniquely determined.
$\mathrm{E}$
18. Notice that the point $(x, y)$ sought is precisely the incenter and excenter of the triangle formed by the line $x+y=2$, the $x$-axis, and the $y$-axis, hence there are four points sought, i.e., (E).