CMA Foundation · Fundamentals of Business Mathematics and Statistics · Quadratic Equations
A rectangular plot of Sharma Traders has a length 3 metres more than its breadth, and its area is 180 square metres. What is the breadth of the plot?
The breadth is 12 metres. With breadth x and length x + 3, the area gives x² + 3x − 180 = 0, which factorises as (x + 15)(x − 12) = 0. The negative root is rejected, so x = 12 and the length is 15 metres.
- A12 metresCorrect
- B15 metres
- C9 metres
- D10 metres
Explanation
Let breadth = x, so x(x + 3) = 180, giving x² + 3x − 180 = 0. Factorising: (x + 15)(x − 12) = 0, so x = 12 (rejecting −15). Check: 12 × 15 = 180. The value 15 is the length, not the breadth.
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