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प्रश्न
Had Aarush scored 8 more marks in a Mathematics test, out of 35 marks, 7 times these marks would have been 4 less than square of his actual marks. How many marks did he get in the test?
उत्तर
Let the actual marks be x.
According to the question,
7(x + 8) = x2 – 4
⇒ 7x + 56 = x2 – 4
⇒ x2 – 7x – 60 = 0
⇒ x2 – 12x + 5x – 60 = 0
⇒ x(x – 12) + 5(x – 12) = 0
⇒ (x – 12)(x + 5) = 0
⇒ x –12 = 0 or x + 5 = 0
⇒ x = 12 or x = –5
⇒ x = 12 ...[∵ Marks can't be negative]
Hence, Aarush scored 12 marks in Mathematics test.
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