Solve the quadratic equation.

x2+2x–8=0
Write one exact solution in each box. You can add or remove boxes. If there are no real solutions, remove all boxes.

1 answer

To solve the quadratic equation \(x^2 + 2x - 8 = 0\), we can use the quadratic formula:

\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \]

In this case:

  • \(a = 1\)
  • \(b = 2\)
  • \(c = -8\)

Now substitute these values into the formula:

  1. Calculate the discriminant \(b^2 - 4ac\): \[ b^2 - 4ac = 2^2 - 4(1)(-8) = 4 + 32 = 36 \]

  2. Now, substitute back into the quadratic formula: \[ x = \frac{-2 \pm \sqrt{36}}{2(1)} = \frac{-2 \pm 6}{2} \]

  3. This gives us two solutions: \[ x = \frac{-2 + 6}{2} = \frac{4}{2} = 2 \] \[ x = \frac{-2 - 6}{2} = \frac{-8}{2} = -4 \]

Therefore, the exact solutions to the equation \(x^2 + 2x - 8 = 0\) are:

  • \(x = 2\)
  • \(x = -4\)

You can put these solutions in the boxes as follows:

  • Box 1: \(2\)
  • Box 2: \(-4\)