Chapter 3 - Section 3.2 - Problem Solving and Business Applications Using Systems of Equations - Exercise Set - Page 206: 23

$x=45,y=30$

As per the statement: $x+y=75$ and $2.10x+1.60y=(1.90)(75)$ After plugging the variable $x$ form the first equation in the second equation, we get $2.10(75-y)+1.60y=(1.90)(75) \implies -0.50y=-15$ or, $y=30$ Now, $x+30=75 \implies x=45$ Thus, $x=45,y=30$