f(x) = 5 / (x - 2)
g(x) = 2x / (x2 - 4)
f(x) + g(x) = 5 / (x - 2) + 2x / (x2 - 4) = 5 / (x - 2) + 2x / [ (x - 2)(x + 2) ]
= [ 5(x + 2) ] / [ (x - 2)(x + 2) ] + 2x / [ (x - 2)(x + 2) ]
= [ 5(x + 2) + 2x ] / [ (x - 2)(x + 2) ]
= [ 5x + 10 + 2x ] / [ (x - 2)(x + 2) ]
= [7x + 10] / [ (x - 2)(x + 2) ]
(f + g)(-1) = [ 7 · -1 + 10 ] [ (-1 -2)(-1 + 2) ] = 3 / -3 = -1