How to Solve the Expression x² + 8x + 20?

To solve the expression x² + 8x + 20, we first need to find the values of x that will satisfy the equation. This expression is a quadratic equation in the form of ax² + bx + c, where:

  • a = 1
  • b = 8
  • c = 20

We can use the quadratic formula to find the roots, which states:

x = (-b ± √(b² – 4ac)) / 2a

Substituting the values of a, b, and c into the formula:

x = (-8 ± √(8² – 4 * 1 * 20)) / (2 * 1)

This simplifies to:

x = (-8 ± √(64 – 80)) / 2

x = (-8 ± √(-16)) / 2

At this point, we see that the term under the square root (-16) is negative, indicating that the roots are complex. To express the roots, we can write:

√(-16) = 4i (where i is the imaginary unit).

So the solutions become:

x = (-8 ± 4i) / 2

This simplifies to:

x = -4 ± 2i

Thus, the solutions to the equation x² + 8x + 20 = 0 are:

  • x = -4 + 2i
  • x = -4 – 2i

In conclusion, since the discriminant is negative, the equation does not have real roots but instead has two complex roots.

More Related Questions