HELP PLEASE FAST

Question

A kite is 150ft high and end 200ft of string are out. If the kite starts drifting away horizontally at the rate of 4 miles an hour, how fast is the string being paid out at the start

Answer 1

let x: horizontal dist from end to kite and let s: length of string

s² = x² + 150² ; s = 200 , x = 50√7 , dx/dt = 4 mph , ds/dt = ?

2s·ds/dt = 2x·dx/dt ...