This is a college level linear algebra problem I am preparin

This is a college level linear algebra problem. I am preparing for a test next week. This is one of the problem example my professor told us to practice. Please show details so I can really understand the problem and thank you very much! I appreciate your help!

Determine whether or not the following system is consistent. If so, use Worth 6 points linear algebra to find the general solution. -4x1 + 8x2-6T3 = -6 2x1-6x2 8x3 = 20