A teacher named Sumi.s from the Kerala university college of teacher education presented on the topic of square difference in mathematics for standard VIII. The presentation covered taking a rectangular region, cutting it into two pieces, separating the pieces and rearranging one piece to form a larger rectangle. By calculating the areas of the original region and rearranged rectangle, the formula a2 – b2 = (a + b)(a - b) was derived.

1. WELCOME

2. Presented by
Sumi . s
Reg.no:13973019
Kerala university college of teacher
education,kollam

3. Name of the techer : Sumi.s
standard: VIII
Subject: Mathematics
unit : Algebra
Topic: Square difference

4. A cut is made splitting the region into two
rectangular pieces
a
b
a

5. Separate this two rectangles
a
a-b
a-b
b

6. The larger piece, has width a and height a-b
a
a-b

7. The smaller piece has width a-b and height b
a-b
b

8. The smaller piece can be detached, rotated and
placed into the right of the larger piece. The two
pieces together form a rectangle, whose width is
a+b and height a-b
a b
a-b
This rectangle’s area is (a + b)(a - b)

9. This rectangle’s area is same as the original figure
There for,
a2 – b2 = (a + b)(a - b)