Solve −2x^2+3x−1=−2

using the quadratic formula. Round the solution(s) to the nearest hundredths. Enter the smaller solution first.

1 answer

To solve the equation

\[ -2x^2 + 3x - 1 = -2, \]

we first rearrange the equation into standard quadratic form by adding 2 to both sides:

\[ -2x^2 + 3x + 1 = 0. \]

Next, we identify the coefficients \(a\), \(b\), and \(c\):

\[ a = -2, \quad b = 3, \quad c = 1. \]

The quadratic formula is given by:

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

Now, we calculate the discriminant (\(b^2 - 4ac\)):

\[ b^2 - 4ac = 3^2 - 4(-2)(1) = 9 + 8 = 17. \]

Since the discriminant is positive, there will be two real solutions. Now we can substitute \(a\), \(b\), and the discriminant into the quadratic formula:

\[ x = \frac{-3 \pm \sqrt{17}}{2(-2)} = \frac{-3 \pm \sqrt{17}}{-4}. \]

This simplifies to:

\[ x = \frac{3 \mp \sqrt{17}}{4}. \]

Now we calculate the two solutions:

  1. For the positive case:

\[ x_1 = \frac{3 + \sqrt{17}}{4}, \]

  1. For the negative case:

\[ x_2 = \frac{3 - \sqrt{17}}{4}. \]

Next, we calculate \(\sqrt{17} \approx 4.123\):

  1. For \(x_1\):

\[ x_1 = \frac{3 + 4.123}{4} = \frac{7.123}{4} \approx 1.78075. \]

  1. For \(x_2\):

\[ x_2 = \frac{3 - 4.123}{4} = \frac{-1.123}{4} \approx -0.28075. \]

Now rounding both solutions to the nearest hundredths:

\[ x_1 \approx 1.78, \quad x_2 \approx -0.28. \]

Finally, we list the solutions in ascending order:

\[ \boxed{-0.28} \quad \text{and} \quad \boxed{1.78}. \]