The given figure of school library is ABCDEF.
where, FA = 15ft, BC = 7ft, CD = 12ft, EF=6ft
For the area of the given figure, extend the line CD upto G, such that DG = 6ft.
Area of the ABCDEF = Area of rectangle ABCG + Area pf DEFG
For ABCG, BC = 7ft,
CG = 6 + 12
= 18 ft
Area of rectangle = Length x breadth
Area of rectangle ABCG = 18 x 7
Area of rectangle ABCG = 126 ft²
For DEFG,
EF = 6ft,
FG = FA - GA
= FA - BC (GA = BC=7)
=15 - 7
FG = 8 ft
Area of recatangle = Length x breadth
Area of rectangle = 6 x 8
Area of rectangle = 48 ft²
Area of the figure ABCDEF = Area of ABCG + Area DEFG
Area of the figure ABCDEF =126 + 48
Area of the figure ABCDEF = 174 ft²
