Answer:
(21-x)/x=1/2
or,42-2x=x
or,42=3x
or,42/3=x
or,x=14
so,the value of x is 14
[tex]\frac{21-x}{x}=\frac{1}{2} \\\\2(21-x)=x\\\\42-2x=x\\\\42=x+2x\\\\3x=42\\\\x=14[/tex]
