Calculate the perimeter of the triangle BCD if BC = 4 cm, CD = 3 cm, AC = 5 cm.

It is known that the perimeter of a triangle (P) is equal to the sum of the lengths of all its sides: P = a + b + c, where a, b, c are the sides of the triangle.
Let’s calculate the perimeter of a given triangle BCD:
P = BC + CD + DB = 4 + 3 + 5 = 12 cm.
Answer: The perimeter of triangle BCD is 12 cm.

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