Answer:
k = -6
Explanation:
Expand by substituting -6:
(n+5) (n-6) = n^2 + 5n - 6n (-6×5)
Thus, (n+5)(n-6) = n^2 -1n -30
(In a facotrised form for quadratics, the numbers need to add to 'bx', in this case -1, and multiply to form 'c' (-30). So -6×5 = -30 and k= -6)