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Hello.
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So here we have given system of equations.
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So what we're going to do is first find the determinant d of the coefficients of the variables.
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So d is equal to the two by two determinants where our coefficients are three, negative six, five, and four.
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We take the determinant of this two by two.
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That's just equal to three times four, which is 12 and then minus negative six times five.
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So that's minus a negative.
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Of 30, which is plus 30.
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So 12 plus 30 is 42.
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So we think d here is equal to 42, right, which is not equal to zero.
00:41
Therefore, yes, we can use kramer's rule.
00:45
That according to kramer's rule, we just get that x is equal to d sub x over d and y is equal to d sub y over d.
00:54
So how do we find d sub x and d sub y? well, d sub x, we just replace the entries in the first column of d with the constants, with the constants here on the right hand side of our system.
01:08
So the d subx is equal to the determinant of now 2412 is our first column.
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And then we have negative 6 .4.
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So we have 24 times 4, which is on 96...