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When 8 is subtracted from the square of a number, the result is 7 times the number. Find the positive solution

User Matteoh
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2 Answers

3 votes
The answer would be 8
User Klaus
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5.3k points
6 votes

Answer:

8

Explanation:

The required relation for number n is ...

n^2 -8 = 7n

n^2 -7n -8 = 0 . . . . subtract 7n

(n +1)(n -8) = 0 . . . . factor

Solutions to this equation are n = -1, or n = 8.

The number is 8.

User Aurelien Ribon
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