I have another question I need help with. How do I solve for the missing angle?

Answer:
The angle measures approximately 18.19°.
Step-by-step explanation:
Since we want to find the angle and we are given the side adjacent to the angle and the hypotenuse, we can use the cosine ratio. Recall that:
[tex]\displaystyle \cos \theta = \frac{\text{adjacent}}{\text{hypotenuse}}[/tex]
The adjacent side is 19 and the hypotenuse is 20. Substitute:
[tex]\displaystyle \cos \theta = \frac{19}{20}[/tex]
We can take the inverse cosine of both sides:
[tex]\displaystyle \theta = \cos^{-1}\frac{19}{20}[/tex]
Use a calculator (make sure you're in Degrees Mode!). Hence:
[tex]\theta \approx 18.19^\circ[/tex]
The angle measures approximately 18.19°.