A rectangular garden is to have an area of . Its length is more than its breadth. Find the length and breadth of the garden.
Answer
Breadth = 10 m, Length = 15 m
The correct answer is Breadth = 10 m, Length = 15 m — Hence breadth m and length m.
Step-by-step solution
- Let the breadth be metres; then length = metres.
- Area = length breadth, so .
- Expand: .
- Factorise the quadratic: find two numbers whose product is and sum ; they are and .
- Rewrite as and factor: .
- Factor out : .
- Set each factor to zero: or . Reject negative breadth, so .
- Hence breadth m and length m.
Common mistake: Taking the negative root as a physical dimension.
Concept tested: Word problem leading to quadratic
Published · How this solution was prepared and checked
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