the question does not present the options, but this does not interfere with the resolution
Let
x------> the length of the swimming pool
y------> the width of the swimming pool
we know that
x=12 ft
y=12-t
the distance between Mike and Ryan is equal to the distance of the diagonal of the rectangular swimming pool
D is the diagonal
D=32 ft-----> D²=32²----> equation 1
D²=x²+y²---> D²=12²+(12-t)²-----> equation 2
equate equation 1 and equation 2
32²=12²+(12-t)²------> 1024=144+(144-24t+t²)
t²-24t-736=0-----> this equation can be used to calculate the values of t
the answer is
the equation t²-24t-736=0
can be used to calculate the values of t