Kaynard's first step in solving this rational equation is to simplify it by multiplying both sides by a common denominator. Which is the simplest expression he can use to do this?
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x^2 - 9 = (x + 3)(x -3)
3x - 9 = 3(x - 3)
and
6
Common denominator would be 6(x+3)(x - 3)
Answer: 6(x+3)(x - 3)