I need help Find the value of c

Answer:
Step-by-step explanation:
From Thales:
[tex]\dfrac{UW}{VX}=\dfrac{WY}{XZ}\\\\\dfrac9c=\dfrac{27}{21}\\\\c\cdot27=9\cdot21\\\\c=\dfrac{9\cdot21}{27}=7[/tex]