Question 251272
2*6=12 ft^2 is the area of the mirror.
(2+2x)(6+2x)=12+9
12+16x+4x^2=21
4x^2+16x+12-21=0
4x^2+16x-9=0
(2x-1)(2x+9)=0
2x-1=0
2x=1
x=.5 ft. is the width of the edge between the morror & the door edge.
Proof:
(2+2*.5)(6+2*.5)=12+9
(2+1)(6+1)=21
3*7=21
21=21