Joined rectangles

You know how to find the area of a rectangle: length times breadth. Today, we will find the area of a figure made of two rectangles joined together. The figure shows Lin's L-shaped panel. Find its area. We draw a dotted line to split the panel into two rectangles. Call the bottom one A and the top one B. A and B fill the whole panel, and they do not overlap. Area of a rectangle is length times breadth. Rectangle A is 11 centimetres long and 3 centimetres broad. 11 times 3 is 33 square centimetres. Rectangle B is 4 centimetres long and 5 centimetres broad. 4 times 5 is 20 square centimetres. Add the two areas. 33 plus 20 is 53 square centimetres. Any figure made of rectangles can be split like this.

The figure shows Lin's T-shaped panel. Find its area. Try it first. Pause if you like. We draw a dotted line to split the panel into two rectangles. Call the bottom one A and the top one B. A and B fill the whole panel, and they do not overlap. Area of a rectangle is length times breadth. Rectangle A is 9 centimetres long and 2 centimetres broad. 9 times 2 is 18 square centimetres. Rectangle B is 3 centimetres long and 5 centimetres broad. 3 times 5 is 15 square centimetres. Add the two areas. 18 plus 15 is 33 square centimetres.

The figure shows Lin's L-shaped panel. Find its area. Try it first. Pause if you like. We draw a dotted line to split the panel into two rectangles. Call the bottom one A and the top one B. A and B fill the whole panel, and they do not overlap. Area of a rectangle is length times breadth. Rectangle A is 9 centimetres long and 3 centimetres broad. 9 times 3 is 27 square centimetres. Rectangle B is 5 centimetres long and 2 centimetres broad. 5 times 2 is 10 square centimetres. Add the two areas. 27 plus 10 is 37 square centimetres. Split the figure into rectangles. Find the area of each one, then add them.