Calculate Parallelogram Side Length: Given 25cm Perimeter and 8cm Side

Let's solve this problem step-by-step:

• Step 1: Understand the problem
  We are given the perimeter of the parallelogram as 25 cm and one side $AB$ as 8 cm. We need to calculate the length of the other side of the parallelogram, $BC$.

• Step 2: Recall the formula for the perimeter of a parallelogram
  The perimeter $P$ of a parallelogram is given by:
  $P = 2(a + b)$
  Where $a$ and $b$ are lengths of adjacent sides.

• Step 3: Apply the given information
  We have $P = 25$ cm and one side $a = AB = 8$ cm. Substitute these into the formula:
  $25 = 2(8 + b)$

• Step 4: Solve for the unknown side $b$
  First, divide both sides by 2:
  $12.5 = 8 + b$
  Subtract 8 from both sides:
  $b = 12.5 - 8$
  $b = 4.5$

• Therefore, the length of the other side is $4.5$ cm.

Upon checking with the given choices, the correct answer is indeed 4.5.