Determining X-axis Intersections Of Quadratic Function Y=2x^2+7x+6

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avigating the realm of quadratic functions, a fundamental question arises: how many times does a given quadratic function intersect the x-axis? This intersection holds significant meaning, representing the roots or zeros of the function, the values of x for which the function y equals zero. In this article, we will delve into the quadratic function y = 2x² + 7x + 6, employing a strategic approach to determine the number of times it graces the x-axis. Our methodology will revolve around a powerful tool known as the discriminant, a key component of the quadratic formula that unlocks the secrets of a quadratic equation's roots. By understanding and applying the discriminant, we can efficiently ascertain whether the function intersects the x-axis twice, once, or not at all, providing us with a comprehensive understanding of its behavior and graphical representation. Let's embark on this mathematical journey, unraveling the mysteries of quadratic functions and their intersections with the x-axis.

Understanding the Significance of x-axis Intersections

Before we dive into the specifics of the given quadratic function, let's take a moment to appreciate the broader significance of x-axis intersections in the world of mathematics and its applications. The points where a function's graph crosses the x-axis, also known as x-intercepts, are not merely graphical features; they represent the solutions or roots of the equation when the function is set equal to zero. In the context of quadratic functions, these roots hold particular importance, as they can reveal valuable information about the function's behavior, its minimum or maximum value, and its overall shape. For instance, in real-world scenarios, the roots of a quadratic equation might represent the time it takes for a projectile to hit the ground, the dimensions of a rectangular area that maximizes space, or the break-even point for a business venture. Understanding the nature and number of these intersections, therefore, equips us with the ability to model and solve a wide array of practical problems.

Furthermore, the x-axis intersections provide crucial insights into the graph of the quadratic function itself. A quadratic function, characterized by its parabolic shape, can intersect the x-axis at two distinct points, indicating two real and distinct roots; at one point, signifying one real root (a repeated root); or at no points, implying that the roots are complex numbers. The position and number of these intersections directly influence the parabola's orientation, its vertex (the minimum or maximum point), and its symmetry. By analyzing the x-axis intersections, we gain a deeper understanding of the quadratic function's characteristics and its relationship to the underlying equation. This understanding is invaluable not only in mathematics but also in various scientific and engineering fields where quadratic functions serve as fundamental models for diverse phenomena.

The Discriminant A Key to Unlocking Intersections

The discriminant is a powerful tool derived from the quadratic formula, serving as a key indicator of the nature and number of roots a quadratic equation possesses. This unassuming yet critical expression resides within the quadratic formula itself, the familiar equation used to solve quadratic equations of the form ax² + bx + c = 0. The quadratic formula, a cornerstone of algebra, provides the values of x that satisfy the equation, effectively revealing the roots of the quadratic function. The discriminant, denoted as Δ (delta), is specifically the expression b² - 4ac, the part nestled under the square root sign in the quadratic formula. Its value holds the secret to determining whether the quadratic function intersects the x-axis twice, once, or not at all.

The magic of the discriminant lies in its ability to discern the nature of the roots without requiring the full computation of the quadratic formula. A positive discriminant (Δ > 0) signals that the quadratic equation has two distinct real roots, implying that the function's graph intersects the x-axis at two distinct points. A discriminant of zero (Δ = 0) indicates that the equation has one real root (a repeated root), meaning the graph touches the x-axis at exactly one point, the vertex of the parabola. Lastly, a negative discriminant (Δ < 0) reveals that the equation has no real roots, but rather two complex roots, signifying that the graph does not intersect the x-axis at all. By simply calculating the discriminant, we gain a swift and efficient way to determine the number of x-axis intersections, saving us the effort of solving the entire quadratic formula when only the number of roots is needed. This makes the discriminant an indispensable tool in analyzing quadratic functions and their graphical representations.

Applying the Discriminant to y=2x^2+7x+6

Now, let's put our knowledge of the discriminant to work by applying it to the specific quadratic function at hand: y = 2x² + 7x + 6. Our goal is to determine how many times this function intersects the x-axis, and we'll achieve this by calculating the discriminant and interpreting its value. Recall that the discriminant, Δ, is given by the formula b² - 4ac, where a, b, and c are the coefficients of the quadratic equation in the standard form ax² + bx + c = 0. In our case, we can readily identify the coefficients: a = 2, b = 7, and c = 6.

With these values in hand, we can proceed to calculate the discriminant: Δ = b² - 4ac = 7² - 4 * 2 * 6 = 49 - 48 = 1. We have obtained a discriminant value of 1, which is a positive number. This result holds significant meaning: it tells us that the quadratic equation 2x² + 7x + 6 = 0 has two distinct real roots. Consequently, the graph of the quadratic function y = 2x² + 7x + 6 intersects the x-axis at two distinct points. This confirms that the function has two x-intercepts, indicating that there are two values of x for which the function's value is zero. By employing the discriminant, we have efficiently determined the number of x-axis intersections without needing to solve the entire quadratic equation, showcasing the power and utility of this mathematical tool.

Conclusion Decoding the Intersections

In our exploration of the quadratic function y = 2x² + 7x + 6, we embarked on a journey to uncover the number of times it graces the x-axis. Leveraging the discriminant, a pivotal component of the quadratic formula, we efficiently navigated this task. Our calculations revealed a discriminant value of 1, a positive number that decisively signals the existence of two distinct real roots for the quadratic equation. This, in turn, translates directly to the function's graph intersecting the x-axis at two distinct points. These intersections, the x-intercepts, hold significant meaning as they represent the solutions to the equation when y equals zero, the values of x that make the function's output zero.

This exercise underscores the power and elegance of the discriminant as a tool for analyzing quadratic functions. By simply evaluating the expression b² - 4ac, we gained invaluable insight into the nature and number of roots, avoiding the more laborious process of solving the entire quadratic formula. Our findings not only answer the initial question of how many times the function intersects the x-axis but also contribute to a deeper understanding of the function's behavior and graphical representation. The two x-axis intersections paint a picture of a parabola that crosses the x-axis twice, revealing key characteristics of the function's shape and position in the coordinate plane. This knowledge empowers us to not only solve mathematical problems but also to model and interpret real-world phenomena where quadratic functions play a crucial role.