0:00
Hello.
00:01
So here we're given this system of equations, we have x plus 4y minus 3z equal to 0, 3x minus y plus 3z equal to 0, and x plus y plus 6c equal to 0.
00:13
Okay, well, solving this is not too hard.
00:16
Just look at this and think, okay, what, i mean, what does x and y and z have to be? right? if x and y and z are all zeros, or then we have 0 plus 0 plus 0 is equal to zero in every one of these equations.
00:28
But to use kramer's rule, well, we would do is take the determinant of the 3x 3x where we take the coefficients on all of our variables.
00:39
So that would be 1, 4, negative 3, 3, negative 1, 3, 1, 3, 1, and 6.
00:47
Okay, you could go ahead and expand along the first row here, and you would end up and you would see that the determinant here is going to be equal to 81, which is not equal to 0.
00:57
So therefore, yes, we can use kramer's rule here.
01:02
Okay.
01:03
But if we use kramer's rule, since the determine it's not equal to zero, we can use kramer's rule.
01:13
And kramer's rule says that x is equal to, well, d sub x over d.
01:19
And y is equal to d sub y over d, and z is equal to d sub z over d.
01:25
Okay.
01:28
But we can, i mean, just notice what.
01:30
The equation is to the system...