Explanation:
use power rule of differentiation :
f(x) = xⁿ → f'(x) = nxⁿ-¹
g(x) = -x² + 18
g'(x) = -2x
m = g'(x)
m = g'(2)
m = -4
y - y1 = m(x - x1)
y - 14 = -4(x - 2)
y - 14 = -4x + 8
y + 4x = 22
y = -4x + 22
slope of the tangent line : -4
Subject : Mathematics
Level : SHS
Chapter : Differentiation