Question is in description.

Question

Solve the following system of linear equations by substitution and determine whether the system is consistent, inconsistent, or dependent. If the system is consistent, find the solution.
{−2x + y= -18

{6x + 6y = −18

Answer 1

−2x + y= -18 ... multiply all terms by 3 to give version B below

 

6x + 6y = −18

−6x + 3y= -54  <---- version B

 

Add these equations: result is 9y = -72, so y = -8.

 

Then -2x - 8 = -18 ...substituting in original first equation; therefore -2x = -10, so x = 5  CONSISTENT: (5, -8).