which value of x is a solution to this equation 8x^2 - 2x - 3 = 0

a. 8
b. -0.5
c. -3
d. 4.5

1 answer

To find the solutions to the equation \( 8x^2 - 2x - 3 = 0 \), we can use the quadratic formula:

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

where \( a = 8 \), \( b = -2 \), and \( c = -3 \).

First, calculate the discriminant:

\[ b^2 - 4ac = (-2)^2 - 4(8)(-3) = 4 + 96 = 100 \]

Now, plug the values into the quadratic formula:

\[ x = \frac{-(-2) \pm \sqrt{100}}{2 \cdot 8} \]

This simplifies to:

\[ x = \frac{2 \pm 10}{16} \]

Now, calculate the two potential solutions:

  1. \( x = \frac{12}{16} = \frac{3}{4} = 0.75 \)
  2. \( x = \frac{-8}{16} = -0.5 \)

The solution \( x = -0.5 \) is one of the options provided:

b. -0.5

Thus, the correct answer is b. -0.5.