Answer: -20
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j(x) = -x
j(3) = -3 ... replace every x with 3
h(x) = 4x - 8
h(j(3)) = 4*( j(3) ) - 8 ... replace every x with j(3)
h(j(3)) = 4*(-3) - 8 ... replace the j(3) on the right side with -3
h(j(3)) = -12 - 8
h(j(3)) = -20