The following system of linear equations
7x + 6y – 2z = 0
3x + 4y + 2z = 0
x – 2y – 6z = 0, has
Solution
Given
<br>7x + 6y – 2z = 0 .......(1)<br>
3x + 4y + 2z = 0 ......(2)<br>
x – 2y – 6z = 0 .......(3)
<br><br>$\Delta$ = $$\left| {\matrix{
7 & 6 & { - 2} \cr
3 & 4 & 2 \cr
1 & { - 2} & { - 6} \cr
} } \right|$$
<br><br>= 7(–24 + 4) – 6(–18 – 2) – 2(–6 – 4) = 0
<br><br>$\therefore$ $\Delta$ = 0
<br><br>The system of equation has infinite non-trival solution.
<br><br>Also adding equation (1) and 3$\times$(3), we get
<br><br>10x = 20z
<br><br>$\Rightarrow$ x = 2z
About this question
Subject: Mathematics · Chapter: Matrices and Determinants · Topic: Types of Matrices and Operations
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