I can't seem to figure out this system of complex numbers, the method I am trying is taking way too long. Is there any quicker way? (doing it by hand, solving for X and Y)

$\displaystyle \frac{X}{10} + \frac{X-Y}{5 + 15i} = 1$

$\displaystyle \frac{Y}{-10i} + \frac{Y-X}{5+15i} = 0.866+0.5i$

EDIT: Sorry this probably should have gone in Linear Algerba