please find the area of this figure and give me the right answer and explain with this concept

First see triangle AEF
Area of triangle = 1/2?Base? Height
= 1/2?10?6 = 30cm
Now see triangle EBC
Area of triangle=1/2?base? height
=1/2?8?10=40cm
Area of rectangle ABCD =Length? Breadth
= 18cm? 10cm=180cm
Area of shaded portion= Area of rectangle ABCD- Area of triangle AEF+ EBC

=180cm-30cm+40cm
=180cm-70cm
=110cm
Area of shaded portion is 110 cm