x - 2/x + 3 + 10x/ x^2 - 9
State any restrictions on the variables.
The expression has restrictions on the variables in the denominator of the second and third terms, x^2 - 9.
This expression is undefined when the denominator is equal to zero, so we must avoid any values of x that would make the denominator equal to zero:
x^2 - 9 = 0
(x - 3)(x + 3) = 0
x = 3 or x = -3
Therefore, the restrictions on x are: x cannot equal 3 or -3.