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4 votes
Nine times the square of a number plus 8 is 44. The number is positive. What’s the number?

User Vishnu Y
by
6.5k points

1 Answer

7 votes

Answer:

n = 4

Explanation:


n-number,\ n>0\\\\9n^2+8=44\qquad\text{subtract 8 from both sides}\\\\9n^2+8-8=44-8\\\\9n^2=36\qquad\text{divide both sides by 9}\\\\(9n^2)/(9)=(36)/(9)\\\\n^2=4\iff n=\pm\sqrt4\\\\n=\pm4

User Psmears
by
6.5k points
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