12x-2y=1; y=6x-8

Question

slove by substitution

Answer 1

The second equation gives you an expression for y.  So substitute that express back for y in the first equation:

 

12x-2y=1

y=6x-8

 

12x - 2(6x-8) = 1

12x - 12x + 16 = 1

16 = 1

 

This can't be true.  Therefore there is no solution.