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Vectors and matrices — Question 5

QCAA 2024, Paper 1 · 1 mark

Q5 · 2024 · Technology-freeSimple familiar1 mark

QUESTION 5

The augmented matrix shown is produced when a Gaussian elimination technique is used to solve a certain system of equations with three variables: [142−1002050032]\left[\begin{array}{ccc|c}1&4&2&-10\\0&2&0&5\\0&0&3&2\end{array}\right]. Given that row 1 values of the matrix represent x+4y+2z=−10x+4y+2z=-10, the unique solution for yy is
(A)
25\dfrac25
(B)
23\dfrac23
(C)
32\dfrac32
(D)
52\dfrac52
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