#### Answer

$x=17000,y=3000$

#### Work Step by Step

Given: $x+y=20000$ and $0.12x-0.05y=1890$
After plugging the variable $x$ form the first equation in the second equation, we get
$0.12(20000-y)-0.05y=1890 \implies -0.17y=-510$
or, $y=3000$
Now, $x+3000=20000$
or, $x=20000-3000=17000$
Thus, $x=17000,y=3000$