The difference of a and b is?
-always rational
-sometimes rational
-never rational
the product of a and b is ?
- always rational
- sometimes rational
- never rational
the square root of ab is?
- always rational
- sometimes rational
- never rational

i do believe it is c 30.0ft

answer

(9y⁹ + x) / (15x⁶y⁹ + xy⁶)

explanation

(9x⁻¹ + y⁻⁹)/(15x⁵ + y⁻³)  

multiply both the numerator and denominator by x

x(9x⁻¹ + y⁻⁹)/x(15x⁵ + y⁻³)   = (9 + xy⁻⁹) / (15x⁶ + xy⁻³)

multiply both the numerator and denominator by y⁹

y⁹(9 + xy⁻⁹) / y⁹(15x⁶ + xy⁻³) = (9y⁹ + x) / (15x⁶y⁹ + xy⁶)