Answer: -10
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Work Shown:
(g-h)(x) = g(x) - h(x)
(g-h)(x) = (2x-4) - (x+2)
(g-h)(x) = 2x-4 - x - 2
(g-h)(x) = x - 6
(g-h)(-4) = -4 - 6
(g-h)(-4) = -10
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An alternative method:
g(x) = 2x-4
g(-4) = 2(-4)-4
g(-4) = -8-4
g(-4) = -12
h(x) = x+2
h(-4) = -4+2
h(-4) = -2
(g-h)(-4) = g(-4) - h(-4)
(g-h)(-4) = -12 - (-2)
(g-h)(-4) = -12 + 2
(g-h)(-4) = -10