How can we find the real solutions of the equation x² + 2x + 2 = 0 by graphing?

Finding Real Solutions by Graphing

To find the real solutions of the quadratic equation x² + 2x + 2 = 0 through graphing, we first need to understand the basic characteristics of the parabola represented by this equation.

Step 1: Understand the Equation

The given equation can be rewritten in standard form, showing the values of a, b, and c: where a = 1, b = 2, and c = 2. This means the parabola opens upwards, since a is positive.

Step 2: Determine the Vertex

The vertex of the parabola can be found using the formula x = -b/(2a). Plugging in our values:

  • x = -2/(2 * 1) = -1

To find the y-coordinate of the vertex, substitute x = -1 back into the equation:

  • y = (-1)² + 2(-1) + 2 = 1 – 2 + 2 = 1

Thus, the vertex is at the point (-1, 1).

Step 3: Graph the Equation

Plot the vertex on the Cartesian plane. Since the vertex is at (-1, 1) and the parabola opens upwards, it will be symmetric around the line x = -1. Draw the parabola by choosing additional points on either side of the vertex. We can calculate a few points:

  • For x = -2:
    y = (-2)² + 2(-2) + 2 = 4 – 4 + 2 = 2 → Point (-2, 2)
  • For x = 0:
    y = (0)² + 2(0) + 2 = 2 → Point (0, 2)

Plotting these points along with the vertex gives a clearer shape of the parabola.

Step 4: Analyze the Graph

From the graph, we can observe that the parabola does not cross the x-axis. Since the y-coordinate of the vertex is 1, which is above the x-axis, it signifies that there are no real roots for this equation.

Conclusion

The quadratic equation x² + 2x + 2 = 0 does not have real solutions, as confirmed by the graph which shows that the parabola does not intersect the x-axis.

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