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5|x + 8| + 15 < 55

for some reason I literally cant get this one inequality right, i looked up the answer but I want to know *how*

User Yarix
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1 Answer

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Answer: the solution to the inequality 5|x + 8| + 15 < 55 is -16 < x < 0.

Explanation:

To solve the inequality 5|x + 8| + 15 < 55, we need to isolate the absolute value expression and then solve for x.

First, we can start by subtracting 15 from both sides:

5|x + 8| < 40

Next, we can divide both sides by 5:

|x + 8| < 8

Now we have two cases to consider, depending on whether x + 8 is positive or negative.

Case 1: x + 8 ≥ 0

In this case, the absolute value expression can be simplified to |x + 8| = x + 8. Substituting this into the inequality, we get:

x + 8 < 8

Simplifying this expression, we get:

x < 0

So the solution for this case is x < 0.

Case 2: x + 8 < 0

In this case, the absolute value expression can be simplified to |x + 8| = -(x + 8). Substituting this into the inequality, we get:

(x + 8) < 8

Simplifying this expression, we get:

x < 16

Multiplying both sides by -1 (and reversing the inequality), we get:

x > -16

So the solution for this case is -16 < x.

Putting the solutions for both cases together, we get:

-16 < x < 0

User Vmayorow
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