ten times the sum of half a number and 6 is 18
\(( \frac{c}{2} + 6) * 10 = 18\)\(( \frac{c}{2} + 6) = \frac{18}{10}\)\(\frac{c}{2} = \frac{18}{10} - \frac{6}{1}\)\(\frac{c}{2} = - \frac{21}{5}\)\(C = - \frac{21}{5} * 2\)\(C = - \frac{42}{5}\)
