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??? I really dont understand this i keep getting it wrong someone plzz help im tryna graduate

??? I really dont understand this i keep getting it wrong someone plzz help im tryna-example-1
User Cheezsteak
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1 Answer

6 votes

Hello!

There are two ways to address this problem. The most efficient way is to solve for u. Another way is to substitute the values from the first column of the table into the given equation, 1 - 5u > -44, solve, and then determine if the side of the left is greater than the right side.

Solving for u:

1 - 5u > -44 (subtract 1 from both sides)

-5u > -45 (divide both sides by -5)

u < 9

Notice that the inequality sign is flipped. If you divide by a negative number, the inequality sign has to flip the other way. < → >, > → <, ≤ → ≥, or ≥ → ≤.

Since u is less than 9, any numbers less than 9 make this equation true.

1. 10 < 9, this is not a solution.

2. 9 < 9, this is not a solution.

3. -10 < 9, this is a solution.

4. 7 < 9, this is a solution.

Substitution Method:

When u = 10, 1 - 5(10) > -44

1 - 50 > -44

-49 > -44 | u = 10 is not a solution.

When u = 9, 1 - 5(9) > -44

1 - 45 > -44

-44 > -44 | u = 9 is not a solution.

When u = -10, 1 - 5(-10) > -44

1 + 50 > -44

51 > -44 | u = -10 is a solution.

When u = 7, 1 - 5(7) > -44

1 - 35 > -44

-34 > -44 | u = 7 is a solution.

As seen above, using both methods can achieve the same solution. So therefore, the answer is no, no, yes, and yes.

User Shiori
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