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