00:01
Alright, so i see that you need help with this question.
00:02
So we have x plus y plus 3z equals 6.
00:06
And then we have x minus 2y equals 5.
00:11
And then we have 2x minus 2y plus 5z equals 9.
00:17
And so for this, we have x minus 2y.
00:21
I'm sorry, x, i'm going to solve for x, equals 5 plus 2y.
00:26
And so i have 5 plus 2y minus y plus 3z equals 6.
00:34
So then i have 5 plus y plus 3z equals 6.
00:42
And so i have y plus 3z equals 1.
00:45
Then i have 2 times 5 plus 2y minus 2y plus 5z equals 9.
00:54
And so 10 plus 4y minus 2y plus 5z equals 9.
01:01
And so we have 2y plus 5z equals negative 1.
01:09
So then i have y plus 3z equals a positive 1.
01:14
So if i multiply, say, this by negative 2, so then i have negative 2y plus 6z equals negative 2.
01:30
And then i have 2y plus 5z equals negative 1...