Respuesta :

Answer:

c = 1

Step-by-step explanation:

[tex]c(9 - 2) \cdot 3=21\\\\\mathrm{Divide\:both\:sides\:by\:}21\\\\\frac{c\left(9-2\right)\cdot \:3}{21}=\frac{21}{21}\\\\c = 1[/tex]