can someone help me figure this out

Answer:
The value of tangent Z is
[tex] \frac{3}{4} [/tex]
Note that the question asks for the value of tan z NOT angle z.
Step-by-step explanation:
[tex] \tan(z) = \frac{opposite}{adjacent} = \frac{21}{28} = \frac{7 \times 3}{7 \times 4} = \frac{3}{4} [/tex]