In any triangle, the sum of the internal angle is always up to 180º.
Then, for triangle ABC:
[tex]90º+30º+(x+20º)=180º[/tex]Use it to solve x:
[tex]\begin{gathered} 90º+30º+x+20º=180º \\ x=180º-90º-30º-20º \\ x=40º \end{gathered}[/tex]In the triangle ACD:
[tex]90º+20º+(y+30º)=180º[/tex]Use it to solve y:
[tex]\begin{gathered} 90º+20º+y+30º=180º \\ y=180º-90º-20º-30º \\ y=40º \end{gathered}[/tex]Then, the value for x is 40º and the value for y is also 40º