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If the sum of the roots of the equation (x - p)(2x + ...

If the sum of the roots of the equation (x - p)(2x + 1) = 0 is 1, find the value of x

A.

112

B.

12

C.

-32

D.

-112

Correct answer is A

(x - p)(2x + 1) = 0

2x2 + x - 2px - p = 0

2x2 + x (1 - 2p) - p = 0

2x2 - (2p - 1)x - p = 0

divide through by 2

x2 - (2p1)2x - p2 = 0

compare to x2 - (sum of roots)x + product of roots = 0

sum of roots = 2p12

But sum of roots = 1

Given; 2p12 = 1

2p - 1 = 2 x 1

2p - 1 = 2

2p = 2 + 1 = 3

p = 32

p = 112