Question 1118517
Draw this out and the area of the entire garden+border is (7+2x)(12+2x)=92
84+38x+4x^2=92
4x^2+38x-8=0
2x^2+19x-4=0
x=(1/4)(-19+/-sqrt (361+32)), sqrt (393)=19.82
only positive root is x=0.82/4 meter or 0.205 m or 20.5 cm  width
7.41*12.41=91.96 m^2, rounding error.