MHB How Do You Solve the Absolute Value Equation -3|x+5| + 1 = 7|x+5| + 8?

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The absolute value equation -3|x+5| + 1 = 7|x+5| + 8 simplifies to -10|x+5| = 7, leading to |x+5| = -7/10. Since the absolute value cannot be negative, this indicates a fundamental issue with the equation. Therefore, the conclusion is that there are no solutions to the equation. The negative result confirms that the equation has no valid solutions. The final answer is no solution.
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-3|x+5| + 1 = 7|x+5| + 8 Solution:

-3|x+5| – 7|x+5| = 7
-10 |x+5| = 7
|x+5| = -7/10
x+5 = ±(-7/10)
x = ±(-7/10) – 5

x₁ = -7/10 – 5
x₁ = -57/10

x₂ = 7/10 – 5
x₂ = 2/10
x₂ = 1/5

Correct?
 
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RTCNTC said:
-3|x+5| + 1 = 7|x+5| + 8 Solution:

-3|x+5| – 7|x+5| = 7
-10 |x+5| = 7
|x+5| = -7/10

When you reach this point, then you should observe that you have a problem...can you identify the problem?
 
MarkFL said:
When you reach this point, then you should observe that you have a problem...can you identify the problem?

The problem is |x+5| = -7/10. More clearly, the problem is the negative -7/10.
 
No solution is the answer.
 
I have been insisting to my statistics students that for probabilities, the rule is the number of significant figures is the number of digits past the leading zeros or leading nines. For example to give 4 significant figures for a probability: 0.000001234 and 0.99999991234 are the correct number of decimal places. That way the complementary probability can also be given to the same significant figures ( 0.999998766 and 0.00000008766 respectively). More generally if you have a value that...

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