4.

5.

doesn't belong with the other three because it is irrational number
The other three can be expressed as a ratio between two <span>integers.

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I believe the answer is 7 but I’m 99% sure ,
Sorry if it’s incorrect
Answer:

Step-by-step explanation:
We need to factor out numerator and denominator in order to simplify the rational expression by cancelling common factors.
Numerator : x^3 - 4 x = x (x^2 - 4) = x (x - 2) (x + 2)
Denominator (factoring by grouping):
x^2 - 5 x + 6 = x^2 - 3 x - 2 x + 6 = x (x - 3) - 2 (x - 3) = (x - 3) (x - 2)
Then we can cancel out the common factor (x - 2) in both numerator and denominator, leading to:
x (x + 2) / (x - 3) = (x^2 + 2)/ (x-3)

2016 Olympics that was held in Rio de Janeiro, Brazil.
2018 Olympics that was held in PyeongChang, South Korea.
Answer:
Step-by-step explanation:
yea