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The area of a rectangle is 60 sq cm and length exceeds breadth by 4 cm. Breadth is
A10 cm
B5 cm
C8 cm
D6 cm
Answer & Solution
Correct answer: D. 6 cm
1. Let breadth be b; length = b + 4.
2. Area: b(b + 4) = 60, i.e. b^2 + 4b - 60 = 0.
3. Factor: (b - 6)(b + 10) = 0, take positive b = 6.
4. So breadth is 6 cm.
_Source: Selina Concise Mathematics Class 10, Ch 5 Quadratic Equations (Mistral OCR'd PDF), section on word problems_
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