Find the values of p for which the quadratic equation has equal roots. Also, find these roots.

For a quadratic equation, ax2 + bx + c = 0,


D = b2 – 4ac


If D = 0, roots are equal



D = (7p + 2)2 – 4(7p – 3)(2p + 1) = 0


49p2 + 28p + 4 – 56p2 + 12 – 4p = 0


7p2 – 24p – 16 = 0


7p2 – 28p + 4p – 16 = 0


7p(p – 4) + 4(p – 4) = 0


(7p + 4)(p – 4) = 0


p = -4/7, 4


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