Answer:
a. To find the perimeter of the first figure, we need to add up the lengths of all four sides. If the sides are equal, we can simply multiply the length of one side by 4. Therefore, the perimeter of a square with sides of 21 cm is:
Perimeter = 4 x side
Perimeter = 4 x 21 cm
Perimeter = 84 cm
b. To find the perimeter of the second figure, we need to add up the lengths of all three sides. Since all three sides are equal, we can simply multiply the length of one side by 3. Therefore, the perimeter of an equilateral triangle with sides of 35 cm is:
Perimeter = 3 x side
Perimeter = 3 x 35 cm
Perimeter = 105 cm
c. To find the perimeter of the third figure, we need to add up the lengths of all four sides. Therefore, the perimeter of a rectangle with sides of 6.75 cm and 2.25 cm is:
Perimeter = 2 x (length + width)
Perimeter = 2 x (6.75 cm + 2.25 cm)
Perimeter = 2 x 9 cm
Perimeter = 18 cm
Explanation:
a. To find the perimeter of the first figure (a square with sides of 21 cm), we need to add up the lengths of all four sides. Since all four sides are equal, we can simply multiply the length of one side by 4. Therefore:
Perimeter = 4 x side
Perimeter = 4 x 21 cm
Perimeter = 84 cm
So the perimeter of the square is 84 cm.
b. To find the perimeter of the second figure (an equilateral triangle with sides of 35 cm), we need to add up the lengths of all three sides. Since all three sides are equal, we can simply multiply the length of one side by 3. Therefore:
Perimeter = 3 x side
Perimeter = 3 x 35 cm
Perimeter = 105 cm
So the perimeter of the equilateral triangle is 105 cm.
c. To find the perimeter of the third figure (a rectangle with sides of 6.75 cm and 2.25 cm), we need to add up the lengths of all four sides. Therefore:
Perimeter = 2 x (length + width)
Perimeter = 2 x (6.75 cm + 2.25 cm)
Perimeter = 2 x 9 cm
Perimeter = 18 cm
So the perimeter of the rectangle is 18 cm.