A college is creating a new rectangular parking lot. the length is 0.17 mile longer than the width and the area of the parking lot is 0.039 square mile. find the length and width of the parking lot.

Let
x----------> the length of the parking lot
y----------> the width of the parking lot

we know that
x=0.17+y-------->equation 1
0.039 mi²=x*y---------> equation 2

substitute 1 in 2
0.039=[0.17+y]*y----------> 0.039=0.17y+y²-----> y²+0.17y-0.039=0

using a graph tool-----> to resolve the second order equation
see the attached figure

the solution is 
y=0.13 mi
x=0.17+y------> x=0.17+0.13------> x=0.30 mi

the answer is
 the length of the parking lot is 0.30 miles
 the width of the parking lot is 0.13 miles