Hello, I have been having trouble with these 3 questions that are on my upcoming test. I have tried it many times without getting an answer and I could really use some help.
Here are the questions:
2x - 3y = 5
4y + 2z = -6
5x + 7z = -15
Solve for X Y and Z using substitution or elimination.
EDIT :I Recently tried to use a homework help online service who gave me the answer ( I didnt understand their work though) For this they got x=4 y=1 and z=-5
2x + 3y - z = 9
x - 3y + z = -6
3x + y - 4z = 31
Solve for X Y and Z using substitution or elimination. (Same as before)
6/x - 4/y = 1
-3/x + 3/y = 2
Solve for X and Y (6/x, 4/y , -3/x and 3/y and fractions) using substitution
EDIT: Same homework help (Once again Didn't Understand what the heck their work meant but..) They Got for X=6/11 and Y=2/5
Thank you in advance and please show your work so I can understand it.
MOVED POST TO URGENT SECTION DUE TO TEST TIME CHANGE.