## Elementary Geometry for College Students (6th Edition)

Lets extend AE , BE, DF ,FC and take DG perpendicular to BC Now BCFE is a rectangle EF=BC = 13ft AD = HG = 7ft than BH = GC = 3ft each By pythagoras theorem on right triangle ABH $AB^{2}$ =$BH^{2}$ + $AH^{2}$ $AB^{2}$ = $3^{2}$ + $4^{2}$ $AB^{2}$ = 9 +16 = 25 AB = 5 AB = DC = 5ft The perimeter of ABCD is AB + BC + CD + DA = 5 + 13+5 +7 = 30 ft