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Amad said, "3n is always greater than n + 3." Do you agree with him?

Amad said, "3n is always greater than n + 3." Do you agree with him?-example-1
User Keyona
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2 Answers

5 votes

The answer is D: no, because 3n could be equal to or less than n + 3. Hope this helps! :)

User Thom Lane
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No, because 3n could be equal to or less than n + 3 (option D)

Step-by-step explanation:
\begin{gathered} 3n\text{ is always greater tha n + 3} \\ 3n\text{ > n + 3} \end{gathered}

To determine the correct option, we test with different numbers

let n = -3, -1, 0, 3, 4


\begin{gathered} \text{when n = -3} \\ 3(-3)\text{ > -3 + 3} \\ -9\text{ > 0 ( false)} \\ \\ \text{when n = -1} \\ 3(-1)\text{ > -1 + 3} \\ -3\text{ > 2 (false)} \end{gathered}
\begin{gathered} \text{when n = 0} \\ 3(0)\text{ > 0 + 3} \\ 0\text{ > 3 (false)} \\ \\ \text{when n = 3} \\ 3(3)\text{ > 3+ 3} \\ 9\text{ > 6 (true)} \\ \\ \text{when n = 4} \\ 3(4)\text{ > 4 + 3} \\ 12\text{ > 7 (true)} \end{gathered}

From the above, we can see that depending on the value of n, 3n can be greater than or less than n + 3.

No, because 3n could be equal to or less than n + 3 (option D)

User Viktor Haag
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