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Where is the error in the solution below? Explain what the error is and solve the equation correctly. Be sure to check your answer.

5/x = x − 4
x · 5/x = x − 4
5 = x − 4
x = 9

1 Answer

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Answer: The error in the solution is that when multiplying both sides of the equation by x, you didn't take into account that x could be equal to zero. Dividing by zero is undefined, so it's important to check if the solution satisfies this condition.

Explanation:

Here's the correct way to solve the equation:

Starting with the equation:

5/x = x - 4

First, we'll multiply both sides by x to eliminate the fraction:

5 = x^2 - 4x

Now, we have a quadratic equation. To solve it, we'll move all terms to one side and set the equation equal to zero:

x^2 - 4x - 5 = 0

Now, we can factor this quadratic equation:

(x - 5)(x + 1) = 0

To find the values of x, we set each factor equal to zero:

x - 5 = 0

x = 5

x + 1 = 0

x = -1

So, the solutions to the equation are x = 5 and x = -1.

However, remember that we initially had a fraction with 5/x. We must check if x = 0 is a valid solution:

If x = 0:

5/0 is undefined, so x = 0 is not a valid solution.

Therefore, the correct solution to the equation is x = -1.

User Donclark
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