PLS HELP ASAP!! need the answer

If you could answer these your a life saver

The maximum distance (in nautical miles) that a radio transmitter signal can be sent is represented by the expression 1.23h√, where h is the height (in feet) above the transmitter. estimate the maximum distance x (in nautical miles) between the plane that is receiving the signal and the transmitter. round your answer to the nearest tenth.

K-7/4=11 explanation: k-7 is the numerator and 4 is the denominator then right by it it just says = 11 ( i wish i knew how to do this but ummm i cant sis)