We know that ∠1 equals ∠3, from that we can find x:
[tex]10x = 100 \\ x = 10[/tex]
The sum of ∠1 and ∠2 must equal 180°:
[tex]10x + 10y + 20 = 180[/tex]
Since we already know x, we can solve for y:
[tex]10 \times 10 + 10y + 20 = 180 \\ 10y + 120 = 180 \\ 10y = 60 \\ y = 6[/tex]
Result: x=10, y=6
