Q1 of 31 Page 1

Find the value of k, for which one root of the quadratic equation kx2 – 14x + 8 = 0 is six times the other.

Given quadratic equation:


kx2 – 14x + 8 = 0


We know that roots of a quadratic equation ax2 + bx + c, a ≠ 0 are



For given equation:


a = k


b = –14


c = 8


Let the roots of above equation be α and β


Given that,


One root is six times other, therefore


α = 6β


Applying the formula, we get






Squaring both side,


196 – 32k =100


⇒ 32k = 96


⇒ k = 3


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