Solve Each System of Equations by the Substitution Method $7 x - y = 6$

Solve each system of equations by the substitution method. $7 x - y = 6$ $- x - 7 y = 3$

A) $\left( - \frac { 39 } { 50 } , \frac { 27 } { 50 } \right)$
B) $\left( \frac { 9 } { 10 } , - \frac { 3 } { 10 } \right)$
C) $\left( \frac { 39 } { 50 } , - \frac { 27 } { 50 } \right)$
D) $\left( \frac { 9 } { 16 } , - \frac { 13 } { 16 } \right)$
E) no solution