Answer
100 and 400
Work Step by Step
Let the width of parking lot $= x$
Length of parking lot $= 2x+200$
Area $= 40,000$
Area of rectangle = $length\times breadth$
$(2x+200)x=40,000$
Open the brackets,
$2x^{2}+200x=40,000$
Divide the entire equation by 2,
$x^{2}+100x=20,000$
Shift the 20,000 to Left Side.
$x^{2}+100x-20,000=0$
Solve the quadratic by factorizing
$(x+200)(x-100)=0$
Thus, $x= -200 , 100$
Discard the negative value. (length cannot be negative)
Therefore width $= 100$
Length $= 2(100)+200= 400$