Answer:
[tex]\large \sf \boxed{ \sf \dfrac{DE}{AD} }[/tex]
Explanation:
[tex]\sf tan(x) = \dfrac{opposite}{adjacent}[/tex]
Here given angle: 19°
Opposite to this angle: DE
Adjacent to this angle: AD
Hypotenuse to this angle: EA
So ratio of sides that defines tan(19) = opposite/adjacent = DE/AD
