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9 cm _ _ _ _ _ _ _ _ _| || |
| | 9 cm| | | _ _ _ _ _ _ _ _ _|a) Formula of the perimeter of a square is
P = 4 x side
= 4 x 9
= 36 cmb) Formula of the area of a square is
A = side²
= 9²
= 81 cm² _ _
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Small squares are

the side of the original square

x 9 = 3 cm
The perimeter of
one small square =
P = 4 x 3 = 12 cm
Perimeter of 4 squares = 4 x perimeter of one square = 4 x 12 = 48 cm
The area of one small square =
A = 4² = 16 cm²
Area of 4 squares = 4 x area of one square = 4 x 16 = 64 cm²
c) Perimeter of new shapePerimeter of original square + perimeter of 4 squares
36 + 48
84 cmd) Area of new shapeArea of original square + area of 4 squares
81 + 64
145 cm²