00:01
This question is asking us to solve matrix using kramer's rule.
00:07
So this is the kramer's rule.
00:09
So for x, we have two unknown variables and two equations.
00:16
And here, this is the formula for 2x matrix.
00:20
So for x, we have this formula numerator over a denominator, same for y.
00:28
And the denominator cannot be 0.
00:31
That's why i put a, b, c, d is not equal to 0.
00:35
For this determinant, it cannot be zero.
00:42
If you do a times b, negative c times b.
00:45
Okay.
00:46
And i put also the colors to make us serve better.
00:53
So i put red, green, blue.
00:57
And for here, i put blue green, red green.
01:01
Here i put red green.
01:04
Red, blue, red, green.
01:09
So red is the first column of the equations or matrix.
01:14
And green is the second column.
01:18
And blue is the first column, i mean third column.
01:23
Okay, so we go back to our equations, the given equations.
01:30
And here i put also the same color...