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PLEASE HELP!

Explain how solving -7y > 161 is different from solving 7y > -161.

I Need a worded explanation!

2 Answers

3 votes

Hi! Feel free to use either answer.

My answer: It is different because you get a different answer when you multiply or divide when the negative sign is in a different position. If y equals 2, the first inequality is incorrect because -14 is less than 161, not greater. But in the second equation, 14 is greater than -161, so the other inequality is correct. So when the negative sign gets switched/moved around to each number, the positive and negative values of each number swap.

Sample response: Both inequalities use the division property to isolate the variable, y. When you divide by a negative number, like –7, you must reverse the direction of the inequality sign. When you divide by a positive number, like 7, the inequality sign stays the same. The solution to the first inequality is y > -23, and the solution to the second inequality is y <>

Hope this helps!

User Sean Bright
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7 votes
because when we devide both sides by a negative number the more than or less than signs reverse so in first case :

- 7y > 161 ( / - 7) \\ y < - 23
while in second case :

7y > - 161( / 7) \\ y > - 23
User Abdur
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5.2k points