Question

Determine whether the values −1 and 7/3 are solutions to the quadratic equation 3x^2−4x−4=3.(1 point)
Responses

Only x=73 is a solution.
Only x equals Start Fraction 7 over 3 End Fraction is a solution.

Only x=−1 is a solution.
Only x equals negative 1 is a solution.

Both x=−1 and x=73 are solutions.
Both x equals negative 1 and x equals Start Fraction 7 over 3 End Fraction are solutions.

Neither x=−1 nor x=73 is a solution.Neither x equals negative 1 nor x equals Start Fraction 7 over 3 End Fraction is a solution.
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1 answer

To determine whether the values \( -1 \) and \( \frac{7}{3} \) are solutions to the quadratic equation \( 3x^2 - 4x - 4 = 3 \), we first rewrite the equation in standard form by moving all terms to one side:

\[ 3x^2 - 4x - 4 - 3 = 0 \]

This simplifies to:

\[ 3x^2 - 4x - 7 = 0 \]

Now, we will evaluate both \( x = -1 \) and \( x = \frac{7}{3} \) in this equation.

Check \( x = -1 \):

\[ 3(-1)^2 - 4(-1) - 7 = 3(1) + 4 - 7 = 3 + 4 - 7 = 0 \]

So, \( x = -1 \) is a solution.

Check \( x = \frac{7}{3} \):

First, find \( \left( \frac{7}{3} \right)^2 \):

\[ \left( \frac{7}{3} \right)^2 = \frac{49}{9} \]

Now, substitute \( x = \frac{7}{3} \) into the equation:

\[ 3\left( \frac{7}{3} \right)^2 - 4\left( \frac{7}{3} \right) - 7 = 3\left( \frac{49}{9} \right) - \frac{28}{3} - 7 \]

Calculating \( 3\left( \frac{49}{9} \right) \):

\[ 3\left( \frac{49}{9} \right) = \frac{147}{9} \]

Next, convert \( -\frac{28}{3} \) and \( -7 \) to have a common denominator of 9:

\[ -\frac{28}{3} = -\frac{84}{9} \] \[ -7 = -\frac{63}{9} \]

Now substitute:

\[ \frac{147}{9} - \frac{84}{9} - \frac{63}{9} = \frac{147 - 84 - 63}{9} = \frac{0}{9} = 0 \]

So, \( x = \frac{7}{3} \) is also a solution.

Conclusion

Both \( x = -1 \) and \( x = \frac{7}{3} \) are solutions to the equation. Therefore, the correct response is:

Both \( x = -1 \) and \( x = \frac{7}{3} \) are solutions.