By the time you finish reading this page and watching the video, you will understand how to work backward to find the area of squares and rectangles.

Students generally know the formula to find the area of a square or a rectangle. However, not all problems are as easy as requiring you to find the area given the length and width.

In some problems on area, the length or width (or both of them) of the rectangle is not given. You need to look into the picture and work backward to find the area.

Consider the following example.

In the figure above, what is the area of rectangle EBCF ?

Area of rectangle = Length x Width = 5 x BC (or EF ) The key is to notice that BC = EF = AD = 12 Therefore, area of EBCF = 5 x 12 = 60 square units

The recorded session below is based on the same idea. Areas of different portions of a rectangular piece of paper is to be found out. The portions themselves are also squares or rectangles but you need to look into the picture to figure out some of the unknown sides.

Notice how the student got confused in the beginning but recovered well and went on to find the correct answer with a little help.

Geometry homework help - working backward to find the area

Did that make sense? This is exactly how some students send me their math homework and we go over them together.