For what values of k is the system of equations 2k2x + 3y - 1 = 0, 7x - 2y + 3 = 0, 6kx + y + 1 = 0 consistent?

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Concept:

Consider three linear eqaution in two variable:

a1x + b1y + c1 = 0

a2x + b2y + c2 = 0

a3x + b3y + c3 = 0

Condition for the consistency of three simultaneous linear equations in 2 variables:

​​​​

Formula for Quadratic equation:

ax2 + bx + c = 0

x = 

Calculation:

2k2x + 3y - 1 = 0      ....(1)

7x - 2y + 3 = 0      ....(2)

6kx + y + 1 = 0      ....(3)

For consistency of given simultaneous equation,

⇒ 2k2(-2- 3) - 3(7 - 18k) - 1(7 + 12k) = 0

⇒ -10k2 - 21 + 54k - 7 - 12k = 0

⇒ -10k2 + 42k - 28 =  0

5k2 - 21k + 14 =  0

By using the formula,

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