See Area =l*w
A=260 inch^2
put values here length and width is given
260=w*(2w+12)
2w^2+12W=260
GCF (greatest common factor) is 2 means divide it by 2
w^2+6w=130
A)w^2+6w+9=130+9
c=9
B)
w^2+6w+9=139
w^2+3w+3w+9=139
w(w+3)+3(w+3)
(w+3)^2=139
(w+3)^2=(11.78)^2
C) (w+3)^2=(11.78)^2
take sqrt both side
w+3=11.78
w=8.789 inches
w= 8.8 inches