Find all real numbers x such that 18x-9> 9 or 2x-4> -10

What you must do for this case is to solve both inequalities
 We have then:
 18x-9> 9
 We clear x:
 18x> 9 + 9
 x> 18/18
 x> 1
 2x-4> -10
 We clear x:
 2x> -10 + 4
 x> -6/2
 x> -3
 Therefore we have to
 For 2x> -10 + 4
 x belongs (-3, inf)
 For 18x> 9 + 9
 x belongs (1, inf)
The solution that is met for both inequalities is:x belongs (1, inf)

By "x2y2" you most likely meant "x^2y^2," where " ^ " denotes exponentiation.

Replacing x with 3 and y with 3, we get 3^2y^2, or (9)(9), or 81.