I would recommend "Introduction to Linear Algebra," by Gilbert Strang. It is a compact but very helpful textbook reference written by a well-known MIT professor. There is a corresponding online MIT course that is free, so that's a bonus. I am currently using it to study linear algebra with no class or previous experience, and I think it does a solid job of explaining things. Each section in the book has a set of questions for you to work through, and answers to selected questions appear in an appendix at the end of the book.
Hope this helps!
Answer:

Step-by-step explanation:







Answer:
z would be your radius
Step-by-step explanation:
Equation: (x - h)² + (y - k)² = r²
Simply take √r² to find <em>r</em>, your radius.
Answer:
X= 18; Y=15
Step-by-step explanation:
As a student myself working this out I cannot explain how I got the answer but I know it is correct.