posted by Rebecca .
A rectangular lawn measuring 8m by 4m is surrounded by a flower bed of uniform width. The combined area of the lawn and the flower bed is 165m^2. What is the width of the flower bed?
Let w=width of flower-bed.
total area, A
Equate A above to 165 m² to get
x²+12x+32 = 165
and solve for x.
Reject the negative root (-19).