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3x^2-4x=20
Look at the picture and identify as many errors you can.

3x^2-4x=20 Look at the picture and identify as many errors you can.-example-1
User Ali Seyedi
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1 Answer

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The errors include:

  • Incorrect square root calculation
  • Incorrect sign for square root term
  • Incorrect value for discriminant
  • Ignoring the imaginary unit when taking the square root of a negative number

There are several errors in the provided solution to the equation 3x^2 - 4x = 20:

1. Incorrect square root calculation:

The calculation of the square root in the equation is incorrect. The negative sign should be inside the square root, not outside. It should read:

x = (-4 ± sqrt(-4^2 - 4ac)) / (2a)

2. Incorrect sign for square root term:

In the subsequent step, the wrong sign is applied to the square root term. It should be:

x = (-4 ± √(-4)^2 - 4(3)(20)) / (2a)

3. Incorrect value for discriminant:

Following the equation, the discriminant (-4)^2 - 4(3)(20) should be evaluated as -256 instead of -16 - 240.

4. Incorrect square root of a negative number:

The square root of a negative number is imaginary and cannot be represented by a real number. Therefore, the equation has no real solutions.

5. Incorrect conclusion:

The statement "No Solutions" is correct because the equation has no real solutions due to the negative discriminant.

In summary, the errors include:

Incorrect square root calculation

Incorrect sign for square root term

Incorrect value for discriminant

Ignoring the imaginary unit when taking the square root of a negative number

These errors collectively lead to the incorrect conclusion that the equation has no real solutions, which is indeed correct.

User Scott H
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8.2k points