Question

i need a explanation to get the answer:

Answer 1

for the first one

Answer 2

to solve , you use "elimination". However, it is a bit complicated to explain.

Answer 3

Do you mean for you, or in general?

Answer 4

Here is a video by Khan
https://www.khanacademy.org/math/linear-algebra/vectors_and_spaces/matrices_elimination/v/matrices-reduced-row-echelon-form-1

Answer 5

thanks for that

Answer 6

hmm I might need to skip it

Answer 7

you only have to do the first part, and reduce the matrix to row echelon form
(you may not have seen these words before)

write down
2 -3 -2 -7
1 -3 -3 4
1 -2 -1 -3

multiply the first row by -1/2 and add to the second row to get a new 2nd row
multiply the first row by -1/2 and add to the 3rd row to get a new 3rd row

Answer 8

you already have two rows why would you need another

Answer 9

Do you still need help?

Answer 10

yes

Answer 11

If you do that you get another row, but whats that to the solution

Answer 12

phi did it by using a matrix. You may not have learned that yet, but I'm assuming you learned elimination. I'll start it off for you. Your first goal is to eliminate two variables so you can solve for the last one.