For what value of k the number -4 is a zero of the polynomial x2-x-(2k+2) and also find the other zero.

Let px = x2 - x - 2k + 2 be the given polynomial.Since, -4 is the zero of the polynomial px, then     p-4 = 0-42 - -4 - 2k + 2 = 016 + 4 - 2k - 2 = 0-2k + 18 = 0-2k = -18k = 9putting k = 9 in px, we getpx = x2 - x - 20Now, we know that zeroes of px are given by solving the equation px = 0so,px = 0x2 - x - 20 = 0x2 - 5x + 4x - 20 = 0xx - 5 + 4x - 5 = 0x - 5x + 4 = 0x - 5 = 0    or    x + 4 = 0x = 5     or    x = -4So, 5 is the other zero of the given polynomial.

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