Example

Finding the Width of a Rectangular Room Given Its Area

Apply the geometry problem-solving strategy using the rectangle area formula when the area and one dimension are known, requiring division to isolate the unknown.

Problem: The area of a rectangular room is 168168 square feet and the length is 1414 feet. What is the width?

  1. Read: A rectangular room has A=168A = 168 sq ft and L=14L = 14 ft; find the width. Draw and label the figure.
  2. Identify: The width of the rectangular room.
  3. Name: Let WW = the width.
  4. Translate: Write the area formula and substitute the given values:

A=LWA = L \cdot W

168=14W168 = 14W

  1. Solve: Divide both sides by 1414: 16814=14W14\frac{168}{14} = \frac{14W}{14}, which gives 12=W12 = W.
  2. Check: Substitute back: A=1412=168A = 14 \cdot 12 = 168, and 168=168168 = 168 \checkmark
  3. Answer: The width of the room is 1212 feet.

Unlike the perimeter example — which involves only multiplication and addition — this problem requires dividing both sides of the equation by the known length to isolate the unknown width. This demonstrates that when one dimension and the area are known, the area formula becomes a one-step linear equation solved by division.

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Updated 2026-04-21

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