if f(x) = 7x-1 and g(x) = 4/(x-2), solve fg(x) = x

fg(x) = 7(4/x-2) -1 = x

28/(x-2) - 1 = x

28/(x-2) = x +1

28 = (x+1)(x-2)

28 = x2 - x - 2

0 = x2 - x - 30

0 = (x-6)(x+5)   x=6 x=-5

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Answered by Sophie W. Maths tutor

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