anet is trying to solve an equation and gets stuck at x2(2x−1)+3x(2x−1)−4(2x−1)=0 . Which of the following is a complete set of solutions to Janet’s equation?(1 point) Responses −4 , 1 negative 4 , 1 12 , −4 , 1 Start Fraction 1 over 2 End Fraction , negative 4 , 1 12 , 4, −1 Start Fraction 1 over 2 End Fraction , 4, negative 1 12

1 answer

To solve Janet's equation \( x^2(2x - 1) + 3x(2x - 1) - 4(2x - 1) = 0 \), we can start by factoring out the common term \( (2x - 1) \):

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

This gives us two separate equations to solve:

  1. \( 2x - 1 = 0 \)
  2. \( x^2 + 3x - 4 = 0 \)

Solving the first equation:

\[ 2x - 1 = 0 \] \[ 2x = 1 \] \[ x = \frac{1}{2} \]

Solving the second equation using the quadratic formula:

The quadratic formula is given by \( x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \). For the equation \( x^2 + 3x - 4 = 0 \), we have \( a = 1 \), \( b = 3 \), and \( c = -4 \).

Calculating the discriminant:

\[ b^2 - 4ac = 3^2 - 4(1)(-4) = 9 + 16 = 25 \]

Now applying the quadratic formula:

\[ x = \frac{-3 \pm \sqrt{25}}{2(1)} = \frac{-3 \pm 5}{2} \]

Calculating the two possible values:

  1. \( x = \frac{-3 + 5}{2} = \frac{2}{2} = 1 \)
  2. \( x = \frac{-3 - 5}{2} = \frac{-8}{2} = -4 \)

Thus, the complete set of solutions is:

\[ x = \frac{1}{2}, x = 1, x = -4 \]

Now, checking the response options to find the complete set of solutions:

The solution set is \( \frac{1}{2}, -4, 1 \).

The correct response from the options provided is:

Start Fraction 1 over 2 End Fraction, −4, 1.