Q7 of 52 Page 1

Find the value of p for which the roots of the equation px (x-2) + 6 = 0, are equal.

Given,


Roots of the equation are equal,


px(x-2) + 6 = 0


px2 – 2px + 6 = 0 p≠0


Let’s take


a = p


b = -2p


c = 6


b2 – 4ac = 0


∴ (-2p)2 – 4(p)(6) = 0


4p2 – 24p = 0


⇒ 4p(p – 6) = 0


4p = 0 or p – 6 = 0


p = 0 or p = 6


But p cannot be equal to 0


According to the Standard form of quadratic equation;


ax2 + bx + c = 0


a ≠ 0


∴ p = 6


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