What is the sum of the roots of the equation √10-x+3/√10-x-4? (Clarification: 3/√10-x is a fraction. 3 is the numerator and √10-x is the denominator. √10-x+ and -4 are not apart of the fraction.)

Aremote-controlled boat can travel at 4 feet per second in calm water. the boat traveled 48 feet with the current, and then it traveled 16 feet against the current in the same amount of time. how fast is the current?