Solve each of the following systems of homogeneous linear equations:

x + y – 2z = 0


2x + y – 3z = 0


5x + 4y – 9z = 0


Given Equations:


x + y – 2z = 0


2x + y – 3z = 0


5x + 4y – 9z = 0


Any system of equation can be written in matrix form as AX = B


Now finding the Determinant of these set of equations,




= 1(1×(– 9) – 4×(– 3)) – 1(2×(– 9) – 5×(– 3)) – 2(4×2 – 5×1)


= 1(– 9 + 12) – 1(– 18 + 15) – 2(8 – 5)


= 1×3 –1 × (– 3) – 2×3


= 3 + 3 – 6


= 0


Since D = 0, so the system of equation has infinite solution.


Now let z = k


x + y = 2k


And 2x + y = 3k


Now using the cramer’s rule






x = k


similarly,






y = k


Hence, x = y = z = k.


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